UKMT Grey Kangaroo, 2019

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

Five friends all brought some cakes with them when they met. Each of them gave a cake to each of the others. They then ate all the cakes they had just been given. As a result, the total number of cakes they had between them decreased by half. How many cakes did the five friends have at the start?

(A) $20$ (B) $24$ (C) $30$ (D) $40$ (E) $60$

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