Question 1137120
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Each of the five friends gets four cupcakes from the others.<br>
Each of them then eats all the cupcakes he was given; that means each of the 5 friends ate 4 cupcakes -- a total of 20 cupcakes.<br>
If eating those decreased the total number of cupcakes by half, then the total number of cupcakes at the beginning was 40.<br>
ANSWER: There were 40 cupcakes total among the 5 friends at the start.