If we made a table to fill in with the info we have, the rate for Tim would be 4 and the rate for John would be 5. What we are looking for is the time they meet, so t for both. Since d = rt, for Tim that expression is 4t, and for John it is 5t. We also don't know how far each one of them travels individually, only that Tim's distance + John's distance covers the 3 miles. Therefore, our equation is 4t+5t = 3. 9t=3 and t = 1/3 of an hour. 1/3 of an hour is 20 minutes, so choice D.
