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What is the sum of the unique prime factors of 207?
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05 Nov 2017, 23:27
05 Nov 2017, 23:27
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Question Stats:
72% (00:28) correct
28% (00:26) wrong based on 50 sessions
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What is the sum of the unique prime factors of 207?
(A) 23
(B) 26
(C) 29
(D) 69
(E) 207
Kudos for correct solution.
(A) 23
(B) 26
(C) 29
(D) 69
(E) 207
Kudos for correct solution.
Re: What is the sum of the unique prime factors of 207?
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06 Nov 2017, 06:00
06 Nov 2017, 06:00
1
207 is twice divisible by 3 and then by 23, so that it is 207 = 3^2*23. Then, the sum of its unique prime factors is 3+23 = 26.
Answer B
Answer B
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Re: What is the sum of the unique prime factors of 207?
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02 Jan 2018, 06:46
02 Jan 2018, 06:46
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Expert Reply
Bunuel wrote:
What is the sum of the unique prime factors of 207?
(A) 23
(B) 26
(C) 29
(D) 69
(E) 207
(A) 23
(B) 26
(C) 29
(D) 69
(E) 207
Let’s break 207 into prime factors:
207 = 23 x 9 = 23 x 3 x 3
So, the sum of the unique prime factors is 23 + 3 = 26.
Answer: B
