What is the sum of different positive Prime Factor of 550 ?
A 10
B 11
C 15
D 16
E 18
Prime Factor
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- candygal79
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550 = (2)(5)(5)(11)candygal79 wrote:What is the sum of different positive Prime Factor of 550 ?
A 10
B 11
C 15
D 16
E 18
So, the DIFFERENT prime factors are 2, 5 and 11
2 + 5 + 11 = [spoiler]18 = E[/spoiler]
Cheers,
Brent
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Hi candygal79,
There's a math rule called 'prime factorization' that you might occasionally use on the GMAT. The idea is that any positive number can be "broken down" into a bunch of prime numbers that are multiplied together (unless the number is already prime).
eg 10 = 2x5
Here, we're asked to prime factor 550; this can be done in a set of steps.
550 = 55x10
55 = 5x11
10 = 2x5
So 550 = 2x5x5x11
GMAT assassins aren't born, they're made,
Rich
There's a math rule called 'prime factorization' that you might occasionally use on the GMAT. The idea is that any positive number can be "broken down" into a bunch of prime numbers that are multiplied together (unless the number is already prime).
eg 10 = 2x5
Here, we're asked to prime factor 550; this can be done in a set of steps.
550 = 55x10
55 = 5x11
10 = 2x5
So 550 = 2x5x5x11
GMAT assassins aren't born, they're made,
Rich
- Abhishek009
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Find the factors of 550candygal79 wrote:What is the sum of different positive Prime Factor of 550 ?
A 10
B 11
C 15
D 16
E 18
550 = 5^2 X 2 X 11
Now we are required to find only the sum of different positive Prime Factor of the number , so the sum is -
5 + 2 + 11 => 18
Abhishek