Which of the following numbers

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Which of the following numbers

by BTGmoderatorDC » Sun Oct 15, 2017 2:21 pm
Which of the following numbers has the greatest number of distinct prime factors?

A. 165
B. 192
C. 228
D. 330
E. 332

How will i get a prime factor? What should i first?

OA D

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Which of the following numbers

by Brent@GMATPrepNow » Sun Oct 15, 2017 2:29 pm
lheiannie07 wrote:Which of the following numbers has the greatest number of distinct prime factors?

A. 165
B. 192
C. 228
D. 330
E. 332
This requires us to find the prime factorization of each answer choice

A. 165 = (3)(5)(11) --- 3 distinct prime factors
B. 192 = (2)(2)(2)(2)(2)(2)(3) --- 2 distinct prime factors
C. 228 = (2)(2)(3)(19) --- 3 distinct prime factors
D. 330 = (2)(3)(5)(11) --- 4 distinct prime factors
E. 332 = (2)(2)(83) --- 2 distinct prime factors

Answer: D

Cheers,
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Last edited by Brent@GMATPrepNow on Sun Apr 01, 2018 5:39 am, edited 1 time in total.
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by EconomistGMATTutor » Mon Oct 16, 2017 2:30 pm
Which of the following numbers has the greatest number of distinct prime factors?

A. 165
B. 192
C. 228
D. 330
E. 332

How will i get a prime factor? What should i first?

OA D
Hi lheiannie07,
Let's take a look at your question.

To find the greatest distinct prime factors we need to factorize all the numbers in the options.
Prime factors of 165 = 3 * 5 * 11
Distinct Prime factors of 165 = 3, 5, 11
165 has 3 distinct prime factors.

Prime factors of 192 = 2 * 2 * 2 * 2 * 2 * 2 * 3
Distinct prime factors of 912 = 2, 3
192 has 2 distinct prime factors.

Prime factors of 228 = 2 * 2 * 3 * 19
Distinct prime factors of 228 = 2, 3, 19
228 has 3 distinct prime factors.

Prime factors of 330 = 2 * 3 * 5 * 11
Distinct prime factors of 330 = 2, 3, 5, 11
330 has 4 distinct prime factors.

Prime factors of 332 = 2 * 2 * 83
Distinct prime factors = 2, 2, 83
332 has 3 distinct prime factors.

Therefore, 330 has the greatest number of distinct prime factors.
Option D is correct.

Hope this helps.
I am available, if you'd like any follow up.
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by Scott@TargetTestPrep » Fri Nov 22, 2019 11:25 am
BTGmoderatorDC wrote:Which of the following numbers has the greatest number of distinct prime factors?

A. 165
B. 192
C. 228
D. 330
E. 332

How will i get a prime factor? What should i first?

OA D
We can express each answer choice as a product of its prime factors:

A) 165

165 = 5 x 33 = 5 x 11 x 3

165 has 3 distinct prime factors.

B) 192

192 = 8 x 24 = 8 x 8 x 3 = 2^6 x 3^1

192 has 2 distinct prime factors.

C) 228

228 = 4 x 57 = 2^2 x 3 x 19

228 has 3 distinct prime factors.

D) 330

330 = 10 x 33 = 2 x 3 x 5 x 11

330 has 4 distinct prime factors.

E) 332

332 = 4 x 83 = 2^2 x 83

332 has 2 distinct prime factors.

330 has the greatest number of distinct prime factors.

Answer: D

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