Answer:
The ratio of letter-size paper to legal-size paper is 3/2
Explanation:
Ratio
Suppose some quantity has a value X respect to another quantity of value Y, we say that the ratio between them is

That magnitude of the ratio can be greater than one, when X>Y, less than one if X<Y or 1 if they are equal
We are told that a copier contains 60% letter-size paper and 40% legal-size paper. The proportion or ratio of letter-size paper to legal-size paper is

Simplifying

Thus the ratio of letter-size paper to legal-size paper is 3/2