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Re: The greatest common factor (GCF) of 48 and 72 is [#permalink]
Expert Reply
The factors of 48 are 1,2,3,4,6,8,12,16,24,48;

The factors of 72 are 1,2,3,4,6,8,9,12,18,24,36,72.

So, as we can see, the Greatest Common Factor or Divisor is 24, because it is the greatest number that divides evenly into all of them.

D is the answer
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Re: The greatest common factor (GCF) of 48 and 72 is [#permalink]
2
Carcass wrote:
The greatest common factor (GCF) of 48 and 72 is

A. 4
B. 6
C. 12
D. 24
E. 48


48 = (2)(2)(2)(2)(3)
72 = (2)(2)(2)(3)(3)

Prime factors in common = (2)(2)(2)(3) = 24

Answer: D

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The greatest common factor (GCF) of 48 and 72 is [#permalink]
1
We need to find The greatest common factor (GCF) of 48 and 72

Lets solve it using two methods

Method 1: Prime Factorization

48 = 3*16 = \(2^4 * 3^1\)
72 = 8*9 = \(2^3 * 3^2\)

To find the GCF take all the common terms and take their lowest power in all of the above.

=> GCF(48,72) = \(2^3 * 3^1\) = 24

So, Answer will be D

Method 2: Common Division Method

4 | 48, 72
-----------
6 | 12 , 18
------------
__| 2, 3

=> GCF = Product of Common factors = 4*6 = 24

So, Answer will be D
Hope it helps!

To learn more about LCM and GCD watch the following videos



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Re: The greatest common factor (GCF) of 48 and 72 is [#permalink]
GCF is just the primes shared by the two numbers:

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