Problema Solution

Imogenes car traveled 280 mi averaging a certain speed. If the car had gone 5mph faster, the trip would have taken 1 hour less. Find the average spped.

Answer provided by our tutors

d = 280 mi the distance traveled

v = the average speed

t = the time of the trip with average speed v

Since v = d/t follows t = d/v

If the average speed is v + 5 the trip would have taken 1 hour less or t - 1 hours:

t - 1 = d/(v + 5)

plug t = d/v into the last equation:

d/v - 1 = d/(v + 5)

plug d = 280 mi:

280/v - 1 = 280/(v + 5)

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click here to see the equation solved for v

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v = 35 mph

The average speed of the car was 35 mph.