Answer
39.505
Work Step by Step
We are given that Pluto is 3670 million miles from the sun. We are also told that AU is the average distance between Earth and the sun, or 92.9 million miles. Therefore, we can divide Pluto's distance from the sun by 92.9 million miles in order to calculate Pluto's AU from the sun.
$\frac{3670}{92.9}=39.505$