Problema Solution
An athlete runs 8 miles, first at a slower speed and then at a faster speed. The total time spent running is 1 hour. If the athlete runs 1/3 hour at 6 mph, find the second speed.
Answer provided by our tutors
distance = speed * time
1/3 hour was run at 6mph, covering a distance of:
1/3 * 6 = 2 miles
8-2=6
1 - 1/3 = 2/3
so, the athlete then ran 6 miles in 2/3 of an hour:
speed = distance/time
6 / (2/3) = 9
the second speed was 9 mph
distance = speed * time
1/3 hour was run at 6mph, covering a distance of:
1/3 * 6 = 2 miles
8-2=6
1 - 1/3 = 2/3
so, the athlete then ran 6 miles in 2/3 of an hour:
speed = distance/time
6 / (2/3) = 9
the second speed was 9 mph