distance, rate, time

Question

Juan drives to work. Because of traffic conditions, he averages 22 mph. He returns home averaging 32 mph. The total travel time is 2.25 hours. How much time did Juan spend driving to work?

Answer 1

let "t"  be a time in hours he spend driving at work, then ( 2.25-t) hours he spend driving back home,

then the distance he drove at work and back is the same. So, we can make an equation:

22t=32(2.25-t)

22t=72-32t

54t=72

t=1.33 hours

Answer 2

Let W be the time it took to drive to work

Let H be the time it took to drive back home

 

W + H = 2.25

 

22W = 32H

 

W = 32H/22

 

W = 16H/11

 

16H/11 + H = 2.25

 

27H/11 = 2.25

 

H ≈ .92 hours

 

W ≈ 16 * .92/11≈ 1.34 hours