If P represents the product of the first 15 positive integers, then P is not a multiple of
a) 99
b) 84
c) 72
d) 65
e) 57
The answers can be expressed in simpler terms as follows
a) 99 = 9 * 11
b) 84 = 7 * 12
c) 72 = 8 * 9
d) 65 = 5 * 13
e) 57 = 3 * 19
The question is to find the number which is not a factor of P.
so the option e is the one with multiple having number other than (1-15) ie, 19.