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Factors and Multiples Game

Stage: 2, 3 and 4 Challenge Level: Challenge Level:1

At Montsaye Community College in Northamptonshire, Year 8 students have taken on the challenge of finding the longest sequence of numbers that can be crossed out.

Gabrielle and Lauren managed a sequence of 50 numbers:

Makenzie managed to improve on this with a chain of $55$ numbers:


Sophie and Tasmin managed to improve on that:

Gabrielle and Lauren managed to improve on their earlier effort:

And Sophie and Tasmin also managed to do even better!

Abigail from Ridgewood School also managed a chain of 61 numbers:

Abigail's solution

Alfie, Manuel, Jack and Emilio from Newhall School in Chelmsford, Essex, worked as a team to also produce a chain of 61:

Newhall solution

A.H. from Manorfield Primary School has improved on this by finding a chain of $63$ numbers:

Evie from Deansfield Primary School created a chain of 65 numbers:

James from Ridgewood School showed he could do even better:

Linda from Bohunt School also used 68 numbers:


A group of Year 9 students from The Perse School for Girls in Cambridge worked together and managed an even longer chain of numbers:


 Chain of 71


And Claire, of Blackheath High School in London, has managed to improve on that:


Jacky, from Princethorpe College in Rugby, has managed to go one better with a chain of 74:


Jesse from Moriah College in Sydney, Australia also managed a chain of 74 numbers:


Well done to all of you. Do let us know if you can do any better!