Question 1197124
 A stunt driver was needed at the production site of a Hollywood movie. The average speed of the stunt driver's flight to the site was 160 mph, and the average speed of the return trip was 120 mph. Find the distance of the round trip if the total flying time was 7 h. 
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Avg speed of a round-trip is {{{2*v[1]*v[2]/(v[1]+v[2])}}}
Avg speed = 2*160*120/280 = 960/7
d = r*t = (960/7)*7 = 960 miles