SOLUTION: Karin biked at 13 mph for a time but got a flat tire. She then walked at 5 mph. She traveled a total of 93 miles. Had she biked the whole time, she would have gone 117 miles. How m

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Karin biked at 13 mph for a time but got a flat tire. She then walked at 5 mph. She traveled a total of 93 miles. Had she biked the whole time, she would have gone 117 miles. How m      Log On

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Question 276924: Karin biked at 13 mph for a time but got a flat tire. She then walked at 5 mph. She traveled a total of 93 miles. Had she biked the whole time, she would have gone 117 miles. How many hours did she walk?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Karin biked at 13 mph for a time but got a flat tire.
She then walked at 5 mph. She traveled a total of 93 miles.
Had she biked the whole time, she would have gone 117 miles.
How many hours did she walk?
:
Let b = biking time
Let w = walking time
:
Write a distance equation for each scenario
13b + 5w = 93
13(b+w) = 117
:
13b + 13w = 117
13b = 5w = 93
--------------------subtraction eliminates b, find w
0b + 8w = 24
w = 24%2F8
w = 3 hrs walking time
:
:
To check solution find biking time
13b + 5(3) = 93
13b + 15 = 93
13b = 93 - 15
13b = 78
b = 78%2F15
b = 6 hrs on the bike
:
using the all bike equation
13(6 + 3) = 117