sum of all of the different positive prime factors

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by DanaJ » Sun Jun 28, 2009 8:32 am
You need to break up 550 into primes. Here's my approach:

550 = 55 * 10 = (5 * 11) * (2 * 5)

As you can see, there are 3 different prime factors: 2, 5 and 11. Their sum will be 18.

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by Scott@TargetTestPrep » Tue May 08, 2018 10:38 am
mzimmer wrote:Hi,
What is the easiest way to solve this type of problem?

What is the sum of the different positive prime factors of 550?
A. 10
B. 11
C. 15
D. 16
E. 18
To determine the sum of the different positive prime factors of 550, let's break 550 into its prime factorization.

550 = 55 x 10 = 5 x 11 x 5 x 2

The different prime factors of 550 are 5, 11, and 2 and the sum of these prime factors is 5 + 11 + 2 = 18.

Answer: E

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