Question 763340
Alvin can go upstream at a rate of 20 miles per hour and downstream at a rate of 30 miles per hour. One day while Alvin was on the river, he received a call telling him he needs to turn around and come home. So he turned around and went back to his starting point. If his entire trip took 10 hours, how far did he travel on the river?
***
let x=travel time upstream
10-x=travel time downstream
distance=speed*travel time (same for both directions)
..
20x=30(10-x)
20x=300-30x
50x=300
x=6
distance=20x=120
how far did he travel on the river? 120 miles