2001 Gauss 7 Problem 24

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

\textbf{(A)}\ 29\quad \textbf{(B)}\ 30\quad \textbf{(C)}\ 31\quad \textbf{(D)}\ 32\quad \textbf{(E)}\ 33

If there are no answer choices shown, enter a numerical answer.

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