Two cyclists start biking from a trails start 3 hours apart

Two cyclists start biking from a trail\'s start 3 hours apart. The second cyclist travels at 10 miles per hour and starts 3 hours after the first cyclist who is traveling at 6 miles per hour. How much time will pass before the second cyclist catches up with the first from the time the second cyclist started biking?

Solution

After 3 hours, 1st cyclist (at 6 mph) in 18 miles.
Second cyclist travels 4 mph faster than 1st cyclist.
So time to move 18 miles at 4 mph is 4 1/2 hours