Question 804923
At 11 am Mandy begins cycling west averaging 30 mph.  Twenty minutes later Liz leaves from the same point going the same direction averaging 36 mph.  At what time will Liz catch up to Mandy?
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In 20 minutes, Mandy is 10 miles away.
Liz gains on her at 6 mi/hr
10/6 = 5/3 hours = 1 hr 40 minutes
11:20 + 1:40 = 1300 hours = 1 PM