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 4 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?  Pick.
A) 1:4  B) 1:5  C) 2:3  D) 3:2  E) 2:5
The cost price of a mango = 1/5 dollars.   The selling price of a mango from the first stack = 1/4 dollars --&gt; the profit from one mango = 1/4 - 1/5 = 1/20 dollars.   The selling price of a mango from the second stack = 1/6 dollars --&gt; the loss from one mango = 1/5 - 1/6 = 1/30 dollars.   The profit from one mango from the first stack is 4 times the loss from one mango from the second stack. the ratio is   1/20*30/1= 3:2   3:2
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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 4 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?