Puzzle Details

A numismatist decides to divide his coin collection between his children.

The eldest gets 1/2 of the collection, the next gets 1/4, the next gets 1/5, and the youngest gets the remaining 49 coins.

How many coins are in the collection?

Answer: There are 980 coins in the collection.

1÷2 + 1÷4 + 1÷5 + 49

this works out as

490 + 245 + 196 + 49 = 980, as required.

To work the answer out from the question, we observe that:

1÷2 + 1÷4 + 1÷5 = 19÷20

and we know that there were 49 coins left, so 1÷20 of the collection is 49 coins.

Which means that the entire collection is 20 x 49 = 980 coins.

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