Problema Solution

It took 1.8 hours to get to texas on friday. Saturday night it took 2 hours to return. The average speed on Friday was 4 mph slower on friday. What was the average speed on saturday?

Answer provided by our tutors

distance = speed * time


we interpret "The average speed on Friday was 4 mph slower on friday." to mean "The average speed on Saturday was 4 mph slower than it was on Friday."


let 'v' represent the speed on Saturday, then 'v+4' represents the speed on Friday


the same distance is driven, the we set the speed*time expressions equal to each other:

(v+4)1.8 = 2v

solving for 'v' we have v=36


the average speed on Saturday was 36 mph