1991 AHSME Problems/Problem 14

Revision as of 11:51, 13 December 2016 by E power pi times i (talk | contribs) (Solution)

Problem

If $x$ is the cube of a positive integer and $d$ is the number of positive integers that are divisors of $x$, then $d$ could be

(A) $200$ (B) $201$ (C) $202$ (D) $203$ (E) $204$

Solution

Solution by e_power_pi_times_i


Notice that if $x$ is expressed in the form $a^b$, then the number of positive divisors of $x^3$ is $3b+1$. Checking through all the answer choices, the only one that is in the form $3b+1$ is $\boxed{\textbf{(C) } 202}$.

See also

1991 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 13
Followed by
Problem 15
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
All AHSME Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. AMC logo.png