A man walks at a rate of 10 mph. After every ten miles, he rests for 6 minutes. How much time does he take to walk 60 miles? Choose one.
A) 300  B) 318  C) 322  D) 324  E) 390

Rationale: "to cover 60 miles the man needs ( time ) = ( distance ) / ( rate ) = 60 / 10 = 6 hours = 360 minutes . he will also rest 5 times ( after 10 , 20 , 30,40 and 50 miles ) , so total resting time = 5 * 6 = 30 minutes . total time = 360 + 30 = 390 minutes . answer : e ."
Answer: E