How Many Rectangles?

Topics: Starter | Shape

• Mr B Boxall, Saffron Walden County High School
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• My year 10 class think that the puzzle is quite clever because it fools you into a quick answer, but then you start see the puzzle in a bit more depth and more rectangles appear.
  
  We think the answer is 26, but are not 100% sure.
  
  Neil,Lewis,Josh,Connor,Caiman.
• Mrs A Davies, Congleton High School
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• My year 8 class got 26 rectangles, so yes, you are correct.
• 7yM1, Dene Magna
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• My year 7 class found 26 also so we agree too! It's 26!
• Year 8x2, Highfield School
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• We go to the highfield school and are in Year 8, we think that the answer was 26. At first it was difficult becuase we couldn't see the angles in the rectangles, but once we double checked we realised what the answer was.
• Angela Camellari, Cubitt Town School
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• I was workin with a Year 5 class and they managed to find 26 as well. I am very suprised I though there were only 17 myself but then I looked closely and then I thought to see if my class could figure out how many they could but the thing is it took them nearly the whole hour lesson to figure it out!
• Ben Sassoon, Michael Sobell Sinai School Year 4
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• 26 is the answer I did it with my teacher and my class. My teacher's name is Miss Alexander. First we thought it was 5 or 6 or 9 but then we did it properly by drawing a few extra lines and we finished at 26 then we scrolled down and the answer was 26.
• MR OReilly, Ryde high school year 11
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• Our year 11 class found 27 hahaha
• St Cleres School, Miss Denniss
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• Year 9Y3 at St Cleres school can see 17 rectangles!!!
• Mr. Clark, Rawarsh Community School
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• To begin with I was really struggling to keep track of what I had counted and what I hadn't. I read the comments about 26 rectangles and couldn't find them. After a good 15 minutes I found a way that I could keep track and found 26. I think the people who found 27 must have counted something twice (as I also did at one point when I counted 28!)
• 10b4, The Port
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• Year10b4 at Whitby High think that its 26 as well. Especially Liam who is usually wrong. Nice puzzle!
• Mr Booth + year10, Whitby
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• A good puzzle. Fatma and Chelsea got 26 too. Thankyou
• 10x1, Shavington High
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• We only did it as a 5 minute starter and got 23!
• Year 6, Roundwood primary school
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• At first we thought the answer was 14, but we searched further and now have figured that the answer is possibly 27.
• Skye Whittaker (Student), Gosnells Primary School
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• When you look closer to the pattern you can see more than meets the eye to start with. I found 26 rectangles, so I'm gathering its right but I'm not 100% sure!
• Mr Conway, MIddlefield School Gainsborough
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• We found 28 and its correct!
  Year 7 Middlefield school Gainsborough.
• Mr Heeley's Klever Krew, Rawthorpe High, Huddersfield
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• We think 28 and we are clever so we are probably right. Please, please please put us on website and Mr Heeley will donate £5 to Children in Need!
• Mrs Myers, Woldgate College
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• Mrs Myers' ace Year 9 class at Woldgate College got 26! But all our heads hurt now!
• Mr Hanning, Cressex Community School
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• My year eight are very loud - but by some miracle they seemed to get 26 - altough at one point someone found 58! I think they had double vision!
• Mr. H, Mary Hare School
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• Having spent the weekend working on this, we are now past caring! We got 26 mostly and the odd 27. Jason got 24. Well done Jason.
• Miss Davey 9x2, St Andrews High
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• I have done this with 5 different classes and my 9x2 wouldn't give up until we finally found how to get more than 14!
• j.s, wps
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• We also got 26 so I think the person who got 27 must have counted one twice. We found it hard at first and couldn't work out how there was so many there because at first we only counted 12 and then we kept going and managed to find 26.
• Ms Shaheen, Greenford High School
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• My year 7 class (set 2) got 26 and it is 26!
• Miss Nimmo, Park View Community School, Chester-le-Street
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• Well my year 10 class found '52' but only if you look really closely. it didnt take us long to figer it out it was just the case of counting them all and making sure we had not counted any more than once. so over all we found 52.
• Dulcie Rutter and Elle Benjamin, St Benedicts, Bury St Edmunds
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• We found 27 in our Year 9 Class.
• Mr McG and Year 9, Parkside Cullingworth
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• Class thinks 26 or 27 but sir only found 25!
• Class 1D, Linwood High School Renfrewshire
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• We found 25 rectangles and cant see where everyone found the extra one!
• Mr. Ditta and 10B, Stokesley School :)
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• We got 27 and we did it for 10 minutes max. seems we are the best.. anyone think they can beat it? good luck, you'll need it!
• X9, Oakwood Park Grammar School
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• We found 26 rectangles
• Patrick Hillman, Year 8 (1) BIS, Jakarta, Indonesia
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• We have found 26. Anyone who has found 27 or 28 is talking rubbish!
• Useless Mathmatician, Birmingham
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• HELP!! I really can't see 26 rectangles, stuck on something like 15! One comment seemed to say that your are allowed to add in lines?! Is this true? Can someone please help me to see the 26 so I can help my class!
• Mr. Vincent and F3H 2008, Santa Rosa de Lima English Secondary (MACAO)
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• One of our students called Ivy found 31 rectangles and I don't know how ... but that's what she said, we all found 26 rectangles.
  However, we are looking for a complete solution of this.
• Year 11 + Ms. Ralston, Buckingham School
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• Our group found 26 rectangles after counting them individually and writing numbers in each. We are about 95% sure of this answer....
  Please get back to us if you would like to give us some prizes for our correct answer! Thank you! x
• Year 9 + Ms. Ralston, Buckingham School
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• We agreed that the total number is 28 rectangles. We are 90% sure this is the correct answer.
• Mr. Walsh, Blackboys Primary School
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• 26! You must be mad! My Year 2/3 class are exceptionally talented mathematicians and are unconvinced there are more than 15. Please tell us your secrets!?!
• Form 87, Childwall Sports College
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• Could someone please show us where there are 26/27 rectangles? We are a Year 8 class and found 15!
• Mrs. K Winter, Mackie Academy - Stonehaven, Scotland
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• My 2M1 class found 27 rectangles. We found 26 rectangles which had been drawn and one clever student pointed out that the word "rectangle" was also on the screen, so we included that in our total. More like this please - our class really enjoyed it!
• 9Z4, Durrington High School Worthing Sussex
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• My group would have liked a definitive answer.
• Miss K Dewar, Imberhorne School
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• My top set Year 9 class thought there were 6 then changed their minds and said 11, 12, 13,14,15,16,17,18,19 and finally 102
  !!!!!
  We attempted this on Children In Need day
• 8x1, Joseph Swan
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• We found 26 in 5 minutes. Not worth any more effort as we believe that we are right and can't see how anyone could find any more.
• Mearns Primary, Chloe W, Chloe N and Perle P.
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• We are pupils of mearns primary set 2 in P6.21 and we found that there are 30 rectangles we are positively sure we did not go over the rectangles more than once or twice. We just drew it out on paper and then then went over them in pen.
• Mrs J Davies, Yr 11 Ellesmere College
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• My amazing sensational yr 11 class found 26 first then 104 aren't they super duper!?
  Starter done during inspection week. love the starter!
• Mr Goulding and Maths group, Kates Hill Primary School
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• Our year 5 class thinks that it is 26
• Mrs Miziolek & Year 11 set 1 & Year 9 Set 2, St Mark's West Essex Catholic School, Harlow
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• Excellent starter. My classes and I agree that there are 26 rectangles.
• Mr T, Warwickshire
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• Year 9 managed to get 31, but we only spent 3 mins on it. They are an advanced class you know...
• Keira Bible, Crispus Attucks Medical Magnet High School
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• I found 26
• Mrs. Barnard, Folkestone Academy
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• My year 9 class found a range - 13 to 26!!! Typical
• S1 Basic Skills, Lockerbie Academy
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• We think there are 27 rectangles.
• Clint Taylor, Romsey School
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• The best year 8 class in hampshire found 26 so it must be correct!
• Clint Chern, ISB
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• There is more than 26 and I am 100 % sure of that, but I don't know the real amount...
• HAD, Herts
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• My Year 10 class soon got bored trying to count the rectangles. They are not very good at counting from a white board they did their best!!
• S2, Peterhead Academy
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• We only count 14 - it seems like you are cheating by adding extra lines to get 26.
• Yr 8, Howard Middle School
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• Scott in year 8 found 27. The other children thought it was 26.
• Alison Wicks, Seaham School Of Technology
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• My Year 9 class found 26. They are pure belters. They definitely will not be wrong.
• Philip Moore, Framingham Earl High School
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• My Year 9 class found 26 rectangles by splitting it up into basic rectangles, smaller rectangles and overlaps. Using all the results from the other schools made a great lesson on averages and charts.
• Kazzaki, Santa Clara
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• I counted 20 rectangles. Does any know what is the correct answer for sure?
• William-John, Peterhead Academy
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• This is an intriguing but enjoyable puzzle, although at times, I found myself confused I was able to push myself through at find 25.
• Megan Bridge, Broadlands School
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• My year 11 class found 19.
• Mr Walker, Henley-on-Thames
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• My Y8 class took three minutes to guess 26. We can't find the 27th rectangle. Great starter - thanks.
• Year 9, English Martyrs School And Sixth Form College
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• We did this as a starter with my Year 9 class and we think that there are 26 rectangles. The classs liked this very much and found it interesting.
• Class 6D, Wepre School
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• We think 52 is ridiculus!! We are a year 6 class and are sure that there are 26. Jazmin had the idea of putting a blob of bluetack on the whiteboard next to the top left corner of every rectangle. We really can't find the 27th if there is one.
• Miss Rees And 7X3b, Trinity C Of E High School
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• We found 16 rectangles!
• Miss King, Harris Academy South Norwood
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• My year 10 class found 26 rectangles, found it mind boggling but enjoyed it.
  No school can beat us!
• Sean O'C, Port Glasgow
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• I often enjoy challenging my mind when I get home from school with one of these magnificent questions. I found 67 rectangles.
• Year 6, St Paul's C Of E Combined School, Wooburn Green
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• Ben fouond 27 rectangles in 7 minutes. We think this is a record for a year 6 pupil! Come on St Paul's!
• Paul Baybutt, Whitstable Endowed
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• My year 5/6 class found 19.
• Mrs Hunt And LIIIM, The Abbey Junior, Reading
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• We found 23 - where did we go wrong? Although, maybe 23 is the CORRECT answer. Year 6 children.
  Definitely don't think there are 52.
• Mrs C Archer, Sanders Draper School
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• My year 10 class, were intrigued! We couldn't see much at all, then one member of the class -Tom- showed us all!!!!
  We then found 26!
• Becky, Dalry
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• 2M Class from Dalry School in Dumfries and Galloway got 26 rectangles in 3 minutes. Using Activ Studio and colours helped!
• Mrs Beacham, From Huntcliff
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• We had lots of different answers. We thought it was a clever starter.We got as far as 22 rectangles.
• Miss Gibert, Winterbourne International Academy
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• Hi. Year 7 found 35 rectangles. We want to know how many there were?
• Mark Pyle, Warden Park
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• I've definitely found 28, no question. Don't think there are any more.
• AHS, Yr 10
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• Hello from Aylesbury High School Year 10.
  We think we have found 28!
• Mrs. Babb, Woodruff High School, SC
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• Mrs. Babb's 4th period class in Woodruff found 24. They were hungry so we had to stop!
• Allerton Grange School, Leeds, Mrs Stoddart
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• My class got between 25 and 27...........so we think 26!
  Allerton Grange School, Leeds England.
• Year 7 Mr Harrison, Trinity C Of E High
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• Miss Rees is very wrong!
  Year 7 found 26-well done everybody.
• Mr Kelso, Trinity C Of E High
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• We found 18 this time, although one of our group thinks he found more.
• Oasis Academy, Immingham, 9Ma1
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• My wonderful, brilliant, stupendous, fantastic students (their words not mine)- I just think they're great, have found 24 but are still looking for more. Hold on, we have found another one.
• Mr Carradine, Bexhill High
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• 10x1 at Bexhill High found 26 rectangles (apart from Harry who reckons there are 63?!).
• The Roseland Community College, Mrs Haslam
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• My Yr7 class found 27 black rectangles. The final black rectangle was the whole background page. We then investigated the white outlines of the large black rectangles. Although the white lines are narrow they still have a length and a width, so can be counted as rectangles. By doing this we found a total of more than 100 rectangles.
  BEAT THIS IF YOU CAN!!!!!!
• Mr Russell, Eston Park School
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• My class of only 9 pupils found an amazing 28 rectangles. Beat that.
• RHS, Class 7S
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• We eventually found 26!!
• H. Ralston, Buckingham School
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• Our year 8 class (8NB and 8NA) together think we found 24 rectangles total!
• Mr Beech, Whingate Primary
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• Most of us in 3R at Whingate found 26 rectangles but we got as high as 28! I didn't tell 3R at the time but I could only find 20!
• Bill, Manchester Metropolitan University
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• I've counted 28. I just attempted to explain in words where each of the rectangles are which proved a lot harder than I anticipated so I gave up! I'm 100% sure that there are 28 though. I'm gonna use this tomorrow in school.
• Mrs Hill's Marvellous Year 6 Maths Group, Solihull
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• We found 26 rectangles - we're convinced that those who found 28 must have counted two of the rectangles twice.
  We spent a whole lesson investigating all of the shape activities including the triangles and the rectangles; it was great fun!
  Beat that!
• Mrs Bramley's Class, Chalkstone Middle School, Yr6 Set 2
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• We had the highest score of 20 when looking at it for 5 minutes. We like these puzzles.
• Mr Dalgleish, 3OD
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• My class found 27 - with my help. very cleaver puzzle - gets you thinking!!
• Miss Lovell, St Aelreds
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• 7ri from St Aelred's think there 21!!
• St Katherine's School,
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• My Year 10 class have said you are all wrong because we got the right answer (which is less than 26).
• 3TC, Redbridge
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• My year 3 class, 3TC, found 18 and they are great!
• Year 10y2, All Hallows Macclesfield
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• We got 28 by using a system so we know we are right!
• 5L, Judbridge
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• We are convinced that there are 26 rectangles in the puzzle. We triple-checked, and always found the same result. Those who found less, should try combining the smaller rectangles they find. Those who found more, should check that they don't count any rectangle twice.
• Saywers Hall College, Year 11
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• We found 22...I think! Some are saying 27, but the majority agree it is 22. xxx.
• 7s/Ma1, Ashton Park School
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• We found 26 in 5 minutes.
• Jenny Long Hensford, London International School
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• Wow!! brain blower this is ... my yr 4 class took 30 min to figure it out.. we got the answers of 26.. for the first time counted it was 14.
• Mrs Read, Ormiston Victory Academy
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• This was great, but it was frustrating not to have a definitive answer to show the students, we all found 22, so if others have found up to 27 we'd like to know where!!
• Younis, Holy Souls School
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• I think it is 26 rectangles.
• Miss Blundell, Arbroath High School
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• My S2 class are convinced that there are 28 rectangles.
• Crickhowell High School,
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• We also found 26!
• 7 Math And Miss Mather, Augsburg
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• We found that there were 22 rectangles.
• Mrs.Lawson's S2 Class, Kirkcaldy High School
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• We found 26 rectangles, and we wonder whether the people who found 27 have included the screen. That is the only way we can find 27.
• 9ab3, Honley High
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• We think there are 26 rectangles and we are always right - well 99% of the time!
• Year 7, New College Leicester
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• The teacher found 22 but the pupils found 26! well done.
• Selston Arts And Community College, 8 0NA 4
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• We got 27 (not including the whiteboard).
• NHS, 8R
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• We only found 15....can someone explain to us how you get 26?
  Thanks 8R.
• Mr Parrett's Year 7 Maths Class, St Peter's High School, Stoke
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• When we first looked, we saw 5, then 9 then 10. We kept looking and bit by bit we saw more and more until we all agreed the number is 26. Epic starter!
• 8M2, King Arthur's Community School, Wincanton
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• Year 8 class found 26 rectangles, they were all hidden in each other!
  We enjoyed doing the puzzle.
• West Kirby Grammar School, Mr Marley's Maths Class
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• We are West Kirby Grammar School, a year 7 class 1 of the pupils Chloe got 10!
• Miss Miller, Baradene College
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• Year 78DM class at Baradene College thinks - 24 rectangles!
• 7x2, Eltham Hill Technology College
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• We found the puzzle challenging but we did enjoy it. If it had been drawn on a white background we would have printed it off to draw around.
  Thanks for the idea Eltham Hill. A printable version has now been added (see link above). Transum.
• Magen, Motherwell
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• I got 26 by my self and im only in primary 7!
• Mr Shepherd, The St Lawrence Academy, Scunthorpe
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• The answer is 26, as various of my classes eventually discovered with a little logical guidance.
  You can, of course, copy the shape multiple times into "paint" and highlight each individual rectangle in a different colour to get an answer, but a more satisfying method is to remove each piece of the picture once it's used...
  eg. the tall thin rectangle on the right (made of 3 rectangles) contains a total of 6 rectangles - 3 small, 2 medium and 1 large. Having counted those 6, the top of it is no longer useful so it can be removed from the picture, as can the top section of the sides as far as where the lines intercept others. The same logic can be used for the bottom section. It can be removed.
  By removing each line as it is counted the picture gets simpler and easier to fathom. Eventually you reach the answer of 26, assuming you don't twice count a rectangle that was inside the remaining shape.
  Note for the site provider: you need a graphics facility to demonstrate this more efficiently, but hopefully the reader can get the idea.
  PS Great site - keep 'em coming.
• Beardsley And Jones, North Wales
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• We found 26 rectangles.
• Miss Ballard, Westfield Sports College
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• My year 10 class think there is 26 but one student thinks he's found 27.
• Mrs Johnstone, Christ Church Middle School
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• My year 6 think there are 26!
• Dr B. Johnson, Cambridge
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• The way we used this was to not allow for extra lines to be drawn, this seems to be a more logical interpretation of the boundary conditions given.
• Mr. Nordell's Class, Sisters, Or
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• My group rocks- 26 it is! 5 minutes!!!!
• 9wx5, Mark Rutherford School
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• We think it is 26. Which is a bit boring because that's what most people have already written. :).
• Miss Filson, Meols Cop High School
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• My year 9 class were brilliant and after great discussion decided that they too agreed the answer was 26! Well done!
• Miss Miller's Math Class, Baradene College
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• 78NB at Baradene College thinks there are 13 rectangles :).
• Kestrel Class (Y5-6), Smarden Primary
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• We found 23 rectangles, and we can't find any more! How on earth did you find 56??!?!?!
• St. Joseph's Primary School, Dundee
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• Primary 6 found 26 rectangles by working as a team.
• Mrs S-B, John Taylor High School
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• My wonderful class found 24. They are in year 10 but I only gave them 5 mins.
• Mrs Ellis 11B2, Granville Sports College
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• We also found 26 rectangles. I must say my year 11 only woke up when they knew how many to look for!!
• 6B Maths Set, Bartley C Of E Junior School
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• We are Bartley C of E Junior School - Year 6 top maths set and we found 14 at first, then Belinda and Hannah pointed out a good tip for finding more and we found 26.
• Jenny, Weston
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• It was challenging, but with teamwork we found 26 rectangles.
• Mrs Uden, Rivermead School, Gillingham
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• We used this today and we have found 27 rectangles in total after lots of discussions and many an error with a whiteboard which needs recallibrating! Love the website.
• Kingfishers, Tranmere Park
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• We had lots of attempts but struggled to find any more than 23! We found it hard to keep track of what we had already counted. It was a very, very tricky puzzle!
• Fulham Prep School, 7N
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• We thought the answer was 26/28. Lol.
• GG, Canada
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• There are 28 rectangles:
  The two upright rectangles has 6 each.
  The rectangle in the middle that has four divisions in it has 10 rectangles.
  Now excluding the 2 upright rectangles and the the rectangle in the middle with 4 divisions:
  The uppermost rectangle has 2.
  The big rectangle on the left has 3.
  The lowest rectangle has 1,
  6 + 6 + 10 + 2 + 3 + 1 = 28.
• Jay, Ft Worth
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• There are only 26.
  The calculations that give 28 are counting 2 duplicates - 1 each for the upright boxes that have 6.
• Lacefie, Singapore
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• Yes it is 26! Surprising how clear it came to me after studying it for a long period of time. And I am from Year 5.
• Mr Stout, Year 5 Lilac Class Kerr Mackie Primary School
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• Lilac Class are loving this as a morning challenge. So far we have found 23 rectangles, but we promise to keep going!
• Gleaming 6x6s, Brookfield
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• Gleaming 6 x 6s from Brookfield thought this was a good starter. The majority found 17, but Shane found 29!!!
• Miss Harris, Somer Primary School
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• My year 6 and 5 class thought this was hard and easy but in 3 minutes and 11 seconds they did it the answer is 26 !!!!
• Year 5, St Patricks
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• We thought it was 27 but Ollie wanted to say 28!
• Year 5/6, Queniborough CofE
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• Our Year 5/6 class found mainly 20+, with our nearest being 25. We would give this a score of 10/10 for challenge, but we really enjoyed as a math starter!
• L4Band L4W, GADS
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• Lower 4 from Gads found all 26!! JK was first.
• Grade 4- St. Stephens, Mr. MacLeod's Class
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• We got twenty-one. Percy, whose birthday is today, said it was the best game ever! Happy birthday buddy!
• Derry, Maine
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• The question should state that the rectangles are overlapping.
• Accelerated English At BSB, Castelldefels
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• Alex (Sasha) only found 20, but we all found 26!
• Senan Yr6, Barnes Primary
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• I found 14 I think that some people get different sheets.
• Miss Crampton, 9G1
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• The Priory School, Shrewsbury
  We found all 26 in just 2 minutes and 19 seconds. We are advanced don't you know...
• Mr Entwistle, James Dixon Primary School
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• My year 4 class found this puzzle a lot of fun and found 26 rectangles (after first thinking there were 5 or 6.).
• Jackie, Willow
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• We think its 13.
• Smithills, Bolton
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• There are 18 rectangles says 11b3!
• Eagles, Derby
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• We found between 11 and 16 with the average being 14.
• Sue, London
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• We think it is 13.
• Paul D, Rougemont School
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• Well we are the bestest maths class ever and are 100% sure the answer is 26.
• 6K Terrigal, Haylee
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• We think 26!!!! But maybe 27????
• Ignacio Larrosa Cañestro, A Coruña (Spain)
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• Very good challenge, requires attention and above all method ..
• Year 7 Maths, Ebor Academy Filey
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• We got 26 in total, 99% certain!
• Miss K Parfett, Abbots Hill
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• I did this with my year 9 and 10 pupils.
  We have found 29.
  We used the word "rectangle", we found the "l" and the square underneath the "?"
  We think we are Super Duper Clever! .
• Mrs Fothergill, UAE
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• My Year 9 class found 24! My favourite all time class - EVER!!!!
• Michelle Cannabe, Canaletto Primary School
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• Hi, my name is Michelle at Canaletto primary school. My Year 3 class say that there is 1 big square on the screen! They are so intelligent! I am very proud of their work.
• Mrs Walker, Woodlands
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• My class think that there are 8 rectangles. They have not included rectangles which have other rectangles cutting through them as their sides are interrupted.

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