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Age 11 to 14

ShortChallenge Level

- Problem
- Solutions

The cake weighed 5 130g.

The range of the guesses (5 040g, 5 060g, 5 110g, 5 120g and 5 150g) is 110 so the two 'wild' estimates must both be low or both high.

Since the difference between 5 040 and 5 060 is 20, 5 040 is 90 out and 5 060 is 70 out.

The range of the guesses (5 040g, 5 060g, 5 110g, 5 120g and 5 150g) is 110 so the two 'wild' estimates must both be low or both high.

Since the difference between 5 040 and 5 060 is 20, 5 040 is 90 out and 5 060 is 70 out.

This problem is taken from the UKMT Mathematical Challenges.

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

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.

A recipe for flapjacks calls for a certain quantity of butter, sugar and oats. Given the amount of these ingredients I have, how many flapjacks can I make?

Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?