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Are You Well Balanced?

Age 5 to 7
Challenge Level Yellow star
Primary curriculum
  • Problem
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Lottie and Adele sent us a great solution to this problem. They answer each part in turn and explain clearly as they go along:

1. To make it balance with 10 on one side, using only one hook, you can put two on the 5 or one on the 10 or five on number 2 or ten on 1.
2. Two weights on the 10=20. So put ten on number 2 hook to make it balance.
3. You could put four weights on the 5 to make it balance with 20 (2 10s).
4. You can put two on the 5 or put five weights on the 2. There is only one solution.
5. It balances by putting one on the 7 (with the 3) and the 10 on the other side.

 

Thank you to you both. I wonder if there are other ways of making it balance if you have one weight on the 10 hook on one side and can use the 3 hook and one other hook on the other side? Don't forget that you can have more than one weight on a hook.

 

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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