GAUSS8 2011 Problem 9

Past Contests GAUSS8 GAUSS (GR. 8) - 2011
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1

There are 15 girls in a class of 27 students. The ratio of boys to girls in this class is

Answer Choices
A. 4:5
B. 5:3
C. 3:4
D. 4:9
E. 9:5