One Digit 100

How many ways can you write an expression for 100 which only uses the same digit repeated and any operations?

One Digit 100

Topics: Starter | Arithmetic | Place Value | Problem Solving | Puzzles

  • Miss Llewellyn’s set one, Rawthorpe
  •  
  • (5x5)=25 25-5=20 20x5=100 so (5x5-5)x5
  • OpenGate , Czech Republic
  •  
  • Generally: (AAA-AA)/A, you can choose any number between 1-9 instead of A
  • Hannah Loyden (10-3), St John Bosco Liverpool
  •  
  • Suggestion is 55 + 55 - 5 - 5 = 100.
  • 10-3, WHGS Manchester
  •  
  • Denny(11 x 11) - 11 - 11 + 1 = 100
    Musa (ish) 1 + 1 + 1 etc = 100
    Sammi 55 + 55 - 5 - 5
    Dom 22 x 22 -222 - 222 + 22 + 22 + 22 - 2 - 2 - 2.
  • Hethersett Junior School, Hethersett Junior School
  •  
  • 5(5 + 5 + 5 + 5)
    55 + 55 - 5 - 5
    2(22 x 2) + 2 + 2 + 2 + 2 + 2 + 2.
  • Jacob, St John Baptist
  •  
  • Another one is 888-88=800*8=100.
  • Saleem Shah, Furness Primary School
  •  
  • My name is Saleem and i've got 4 solutions
    (5×5)+(5×5)+(5+5)+(5+5)=100
    55+(5×5)+5+5+5+5=100
    (2+2+2+2+2)×22÷2-(2+2+2+2+2)=100
    11×11-11÷(1+1+1+1+1+1+1+1+1+1)=100.
  • Faiz, Hethersett JUnior
  •  
  • (2x2) x 22 +(2x2) + (2x2) + (2x2).
  • Michael, Hethersett Junior
  •  
  • 44 + 44 +(44/4) + 44/44.
  • RIO+ MICHAEL, ROOM 10
  •  
  • 5x5x5-5-5-5-5-5.
  • St Peter's Y6 Maths, UK
  •  
  • We loved this and got loads of good answers - Abi T was our winner.

How did you use this starter? Can you suggest how teachers could present or develop this resource? Do you have any comments? It is always useful to receive feedback and helps make this free resource even more useful for Maths teachers anywhere in the world.
Click here to enter your comments.

Previous Day | This starter is for 4 October | Next Day

 

Answers

Sign in to your Transum subscription account to see the answers


Your access to the majority of the Transum resources continues to be free but you can help support the continued growth of the website by doing your Amazon shopping using the links on this page. Below is an Amazon link. As an Amazon Associate I earn a small amount from qualifying purchases which helps pay for the upkeep of this website.

Educational Technology on Amazon

 

Online Maths Shop

Laptops In Lessons

Teacher, do your students have access to computers such as tablets, iPads or Laptops?  This page was really designed for projection on a whiteboard but if you really want the students to have access to it here is a concise URL for a version of this page without the comments:

Transum.org/go/?Start=October4

However it would be better to assign one of the student interactive activities below.

Laptops In Lessons

Here is the URL which will take them to a related activity.

Transum.org/go/?to=OneDigit

Student Activity

 


Transum.org is a proud supporter of the kidSAFE Seal Program