The ratio of apples to bananas in a box is $3: 2$. The total number of apples and bananas in the box cannot be equal to
(A) 40
(B) 175
(C) 55
(D) 160
(E) 72
Since the ratio of apples to bananas is $3: 2$, then we can let the numbers of apples and bananas equal $3 n$ and $2 n$, respectively, for some positive integer $n$.

Therefore, the total number of apples and bananas is $3 n+2 n=5 n$, which is a multiple of 5 .

Of the given choices, only (E) 72 is not a multiple of 5 and so cannot be the total.

(Each of the other choices can be the total by picking an appropriate value of $n$.)

ANSWER: (E)