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  • Early Years Foundation Stage

Largest Product

Age 11 to 14
Challenge Level Yellow star
Secondary curriculum
  • Problem
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Largest Product printable worksheet
 

Here are some different ways in which we can split 100:

  • $30 + 70 = 100$
  • $20 + 80 = 100$
  • $21 + 56 + 23 = 100$
  • $10 + 10 + 10 + 10 + 10 + 10 + 20 + 20 = 100$

The products of these sets are all different:

  • $30 \times70 = 2100$
  • $20 \times 80 = 1600$
  • $21 \times 56 \times23 = 27048$
  • $10 \times 10 \times 10 \times 10 \times 10 \times 10 \times 20 \times 20 = 400000000$

What is the largest product that can be made from whole numbers that add up to 100?

Choose another starting number and split it in a variety of ways.
What is the largest product this time?

Can you find a strategy for splitting any number so that you always get the largest product?

 

Click here for a poster of this problem.

 

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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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