posted by Katie .
I have been working on this problem for an hour and a half! I keep getting 1.33 but I know that's not right!!
Jim drove the 120 miles to grandmothers house in 3 hours. He increased the speed by 10 miles per hour on the way home. How long did it take him to drive home?
velocity on the way: 120/3 mph
veloicyt on the way back: 120/3 + 10
time to get back: distance/velocity
= 120/(50)=12/5=2 2/5 hrs