Question

Frank drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 7 hours. When Frank drove home, there was no traffic and the trip only took 5 hours. If his average rate was 18 miles per hour faster on the trip home, how far away does Frank live from the mountains?
Do not do any rounding.

Answer 1

rate = distance/time let distance=x
rate +18 = x/5
rate = x/7
a) x = 5 * rate + 90
b) x = 7*rate

multiplying a) by -1
a) -x = -5rate -90
b) x = 7rate

Adding the equations
2 rate = 90
rate = 45
rate + 18 = 63

distance = 7*45 = 315

Answer 2

angelax0 - what do you think?

Answer 3

thank you

Answer 4

u r welcome