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counting and probability intermediate

Problem

Suppose 2 distinct integers are chosen from 1 through 9, inclusive. What is the probability that they are both odd?
Solution
Let's consider an `outcome' to be a choice of 2 numbers without regard to order. There are ways to choose 2 numbers from our set of 9 if we don't care about order. There are ways to choose 2 numbers from the 5 odd numbers without regard to order. Therefore, the probability is .
Final answer
\frac{5}{18}