greatest common divisor

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greatest common divisor

by arora007 » Wed Dec 29, 2010 3:46 am
If 3 is the greatest common divisor of positive integers r and s, what is the greatest common divisor of 2r and 2s?

(A) 2
(B) 3
(C) 4
(D) 6
(E) 12

[spoiler]The answer is fairly simple!![/spoiler]
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by shovan85 » Wed Dec 29, 2010 4:10 am
GCD(r,s) = 3
GCD(2r,2s) = 2*3 = 6
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by diebeatsthegmat » Wed Dec 29, 2010 5:40 pm
arora007 wrote:If 3 is the greatest common divisor of positive integers r and s, what is the greatest common divisor of 2r and 2s?

(A) 2
(B) 3
(C) 4
(D) 6
(E) 12

[spoiler]The answer is fairly simple!![/spoiler]

hihihih 6?