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Number Detective

Follow the clues to find the mystery number.

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Six Is the Sum

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

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In the multiplication calculation, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?


Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Why do this problem?

This activity is very good for exploring properties of odd (and even) numbers. It can provide an opportunity for pupils to show their skills in perseverance.

Key questions

What have you discovered so far?
Tell me about the numbers you've found.

Possible extension

Learners could explore even numbers and then compare their findings to the odd numbers. Can they explain the results?

Possible support

Many children will find it helpful to have calculators to hand.