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Age 11 to 14
Challenge Level

A man has 5 coins in his pocket.

  • He can make 13 different amounts of money with his coins
  • The amounts of money he can make end with one of two possible digits.
  • He cannot make up exactly 70 pence
  • He cannot afford an item costing 1 pound
  • He can make a prime number bigger than 10 with his coins.

Given these clues, can you work out what the coins are?
Is there only one possible combination of coins?


Remove one of the clues. Are there any new possibilities for the values of the 5 coins?
Replace that clue and remove a different one, work out the new possibilities. Repeat for the other clues.

Can you remove a clue and only end up with your original solution(s)?

Which clues have the biggest impact?

Click here for a poster of this problem.