Pat and Cara begin running at the same time and they start at the same place on a straight path. Pat runs at 9 miles per hour, and Cara runs at 5 miles per hour. After 10 minutes, Pat stops to stretch. If it takes Pat 20 minutes to stretch and Cara continues to run during this time, how many minutes will it take Pat to catch up to Cara?	Answers.
A) 12
B) 15
C) 18
D) 21
E) 24
In 10 minutes, Pat runs 1.5 miles.   In 30 minutes, Cara runs 2.5 miles.   Pat can catch Cara at a rate of 4 miles per hour.   Since Cara is ahead by 1 mile, it will take Pat 1 / 4= 
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>
0.25 hours= 15 minutes to catch Cara.   the answer is 15.
<result>B</result>
Pat and Cara begin running at the same time and they start at the same place on a straight path. Pat runs at 9 miles per hour, and Cara runs at 5 miles per hour. After 10 minutes, Pat stops to stretch. If it takes Pat 20 minutes to stretch and Cara continues to run during this time, how many minutes will it take Pat to catch up to Cara?