**GMAT Paper Tests**

The numbers in which of the following pairs do NOT have a pair of distinct prime divisors in common?

A. 10 and 20

B. 12 and 18

C. 24 and 32

D. 21 and 63

E. 22 and 88

OA C

00:00

**A**

**B**

**C**

**D**

**E**

The numbers in which of the following pairs do NOT have a pair of distinct prime divisors in common?

A. 10 and 20

B. 12 and 18

C. 24 and 32

D. 21 and 63

E. 22 and 88

OA C

- [email protected]
- GMAT Instructor
**Posts:**15562**Joined:**08 Dec 2008**Location:**Vancouver, BC**Thanked**: 5254 times**Followed by:**1266 members**GMAT Score:**770

10 = (2)(5)

20 = (2)(2)(5)

So, 10 and 20 both have 2 as a prime divisor, and they both have 5 has a prime divisor.

In other words, they have a PAIR a prime divisors in common

Eliminate A

12 = (2)(2)(3)

18 = (2)(3)(3)

So, 12 and 18 both have 2 as a prime divisor, and they both have 3 has a prime divisor.

In other words, they have a PAIR a prime divisors in common

Eliminate B

32 = (2)(2)(2)(2)(2)

So, 32 has only ONE distinct prime divisor

As such, it's impossible for 24 and 32 to have a PAIR a prime divisors in common

Answer: C

Cheers,

Brent