A grocery store bought some mangoes at a rate of 5 for a dollar. They were separated into two stacks, one of which was sold at a rate of 3 for a dollar and the other at a rate of 6 for a dollar. What was the ratio of the number of mangoes in the two stacks if the store broke even after having sold all of its mangoes?
A. 1:4
B. 1:5
C. 2:3
D. 1:2
E. 2:5
A. 1:4
B. 1:5
C. 2:3
D. 1:2
E. 2:5