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Coins

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

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?

Extension:

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?

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