Family Fortune
If three brothers will get £20 more if they do not share their money with their sister, how much money is there?
Age
11 to 14
Challenge level
Problem
Three brothers and a sister shared a sum of money equally among themselves. If the brothers alone had shared the money, then they would have increased the amount they each received by £20. What was the original sum of money?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Student Solutions
Answer: £240
Working out the sister's share
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£20 + £20 + £20 = ?
£60 each so £60$\times$4 = £240 altogether
Using fractions
The difference between one third of the sum of money and one quarter of it is £20. So one twelfth of the sum of money is £20.