GAUSS7 2013 Problem 12

Past Contests GAUSS7 GAUSS (GR. 7) - 2013
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1

Which of the following pairs of numbers has a greatest common factor of 20?

Answer Choices
A. 200 and 2000
B. 40 and 50
C. 20 and 40
D. 20 and 25
E. 40 and 80