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# More Less Is More

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Age 7 to 14

Challenge Level

- Problem
- Getting Started
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- Teachers' Resources

This problem follows on from Less is More.

See the Teachers' Resources of Less Is More for guidance on how this problem could be used in the classroom.

*This problem featured in the NRICH Primary and Secondary webinar in November 2022, and in an NRICH student webinar in the same month.*

Choose two digits and arrange them to make two double-digit numbers. Now add your double-digit numbers. Now add your single digit numbers. Divide your double-digit answer by your single-digit answer. Try lots of examples. What happens? Can you explain it?

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?