Answer: 60 mph
Step-by-step explanation:
Question wants the speed to the lake.
It took James 4 hours to get to the lake and he drove at a speed 20 mph faster than when he came back.
It took him 6 hours to come back.
Assuming the speed James used on the return trip is x:
Expression for distance is:
4(x + 20) = 6x
4x + 80 = 6x
2x = 80
x = 80/2
x = 40 mph
Speed to the lake = 40 + 20
= 60 mph
