SOLUTION: Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Jan drove the remainder of the trip and averaged 55 m
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Jan drove the remainder of the trip and averaged 55 m
Log On
Question 178064: Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Jan drove the remainder of the trip and averaged 55 miles per hour. For what length of the time did Chris drive? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first
part of the trip and averaged 35 miles per hour. Jan drove the remainder of
the trip and averaged 55 miles per hour. For what length of the time did Chris drive?
:
let t = length time Chris drove
then
(12.8-t) = length time Jan drove
:
write a dist equation: dist = speed * time
:
C's drive dist + J's drive dist = 618
35t + 55(12.8-t) = 618
:
35t + 704 - 55t = 618
:
35t - 55t = 618 - 704
:
-20t = -86
t =
t = +4.3 hrs Chris drove
:
:
Check solution:
J's time: 12.8 - 4.3 = 8.5 hrs
35(4.3) + 55(8.5) =
150.5 + 467.5 = 618
