Maths Olympiad Prep

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Number theory Difficulty 2.0 Junior Find the answer United Kingdom

In New Threeland there are three types of coins: the 2p; the 5p; and one other. The smallest number of coins needed to make 13p is three. The smallest number of coins needed to make 19p is three. What is the value of the third type of coin?

(A) 4p4p (B) 6p6p (C) 7p7p (D) 9p9p (E) 12p12p

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