How many pairs of positive integers (x,y) have the property that the ratio x:4 equals the ratio 9:y?
Answer Choices
A. 6
B. 7
C. 8
D. 9
E. 10
How many pairs of positive integers (x,y) have the property that the ratio x:4 equals the ratio 9:y?
Answer Choices
A. 6
B. 7
C. 8
D. 9
E. 10