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CEMC Gauss (Grade 7), 2001

Number theory Difficulty 3.0 AMC 10/12 Find the answer Canada

Enzo has fish in two aquariums. In one aquarium, the ratio of the number of guppies to the number of goldfish is $2:3$ . In the other, this ratio is $3:5$ . If Enzo has 20 guppies in total, the least number of goldfish that he could have is

(A) $29$ (B) $30$ (C) $31$ (D) $32$ (E) $33$

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