Bunuel wrote:
2600 has how many positive divisors?
A. 6
B. 12
C. 18
D. 24
E. 48
Kudos for correct solution.
If the
prime factorization of N = (p^
a)(q^
b)(r^
c) . . . (where p, q, r, etc are different prime numbers), then N has a total of (
a+1)(
b+1)(
c+1)(etc) positive divisors.
Example: 14000 = (2^
4)(5^
3)(7^
1)
So, the number of positive divisors of 14000 = (
4+1)(
3+1)(
1+1) =(5)(4)(2) = 40
-----------------------------------
2600 = (2)(2)(2)(5)(5)(13)
= (2^
3)(5^
2)(13^
1)
So, the number of positive divisors of 2600 = (
3+1)(
2+1)(
1+1) =(4)(3)(2) = 24
Answer: D
Cheers,
Brent