A survey on the investment behaviors of a sample of adults produces the findings presented in the Venn diagram below.

A Venn diagram with an unlabeled universal set contains two intersecting circles labeled Stocks and Bonds that divides the universal set into four regions labeled as follows, where the label is given first and the content is given second: Stocks only, 16; Stocks and Bonds only, 12; Bonds only 31; outside the circles only, 8.

Given that a random person from the sample invests in stocks, what is the probability that the person also invests in bonds?

Provide the final answer as a fraction.