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Doughnut Dissection

A puzzle to find four different ways of making 11025 by multiplying together three different numbers.

Level 1 Level 2 Level 3 Level 4 Level 5 Level 6 Level 7 Level 8 Level 9 Level 10 More Puzzles

Type numbers into the squares so that the three numbers along each edge of the doughnut multiply together to give 11025. Each of the numbers should be different and the number one is not allowed.

Doughnut

11025

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This is Doughnut Dissection level 10. You can also try:
Level 1 Level 2 Level 3 Level 4 Level 5 Level 6 Level 7 Level 8 Level 9

Clue: Begin by finding the prime factorisation of 11025 (You may find drawing a Factor Tree is the best way to do this). Next explore the different ways the prime factors can be combined to make three factors.

Doughnut Dissection is adapted from an original idea by Ann Roberts, a Transum Subscriber. Ann would be interested to hear about how many ways people could find to make 900 as the product of three different numbers and without using the number one. You can leave your comment here.

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Comment recorded on the 12 July 'Starter of the Day' page by Miss J Key, Farlingaye High School, Suffolk:

"Thanks very much for this one. We developed it into a whole lesson and I borrowed some hats from the drama department to add to the fun!"

Comment recorded on the 2 May 'Starter of the Day' page by Angela Lowry, :

"I think these are great! So useful and handy, the children love them.
Could we have some on angles too please?"

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