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# No Matter

Think of a whole number, double it, then add 3.

Multiply your answer by 4 and then take away 5.

Now take away the number you first thought of.

Your answer will always be a multiple of which number?

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Age 11 to 14

ShortChallenge Level

- Problem
- Solutions

Think of a whole number, double it, then add 3.

Multiply your answer by 4 and then take away 5.

Now take away the number you first thought of.

Your answer will always be a multiple of which number?

This problem is taken from the UKMT Mathematical Challenges.

You can find more short problems, arranged by curriculum topic, in our short problems collection.

15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

Arrange the numbers 1 to 16 into a 4 by 4 array. Choose a number. Cross out the numbers on the same row and column. Repeat this process. Add up you four numbers. Why do they always add up to 34?

The well known Fibonacci sequence is 1 ,1, 2, 3, 5, 8, 13, 21.... How many Fibonacci sequences can you find containing the number 196 as one of the terms?