shrive555 wrote:

2,600 has how many positive divisors?

A. 6

B. 12

C. 18

D. 24

E. 48

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

----------ONTO THE QUESTION-------------------------

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

_________________

Brent Hanneson – GMATPrepNow.com

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