Task: Question Answering
Input (English): Problem: 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 5 for a dollar and the other at a rate of 5 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 ?
Options: a. 1: 1, b. 1: 5, c. 2: 3, d. 1: 2, e. 2: 5
Output (English): a