On the first part of a trip Bob averaged 60mph but on the se

On the first part of a trip Bob averaged 60mph but on the second part of the trip, which was 50 miles more than the first part, he averaged 40mph. What was the total distance for the trip if the entire trip took 8 hours?

Solution

60x=y and
40*(8-x)=50+y and
z=2y+50
z=374
trip was 374 miles