A class of 30 students wrote a history test. Of these students, 25 achieved an average of $75 \%$. The other 5 students achieved an average of $40 \%$. The class average on the history test was closest to
(A) 46
(B) 69
(C) 63
(D) 58
(E) 71
To calculate the overall class average, we can assume that each of the 25 students who averaged $75 \%$ each actually got a mark of $75 \%$. Similarly, we may assume that the other 5 students each actually got a mark of $40 \%$. So the overall average is

$$
\frac{25(75)+5(40)}{30}=\frac{2075}{30}=69.2
$$

which is closest to 69 of all of the possible choices.

ANSWER: (B)