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
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-> 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
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Question 154887: 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) (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 x = time she biked
Let y = time she walked
:
Write a distance equation for each scenario: Dist = speed * time
13x + 5y = 93
and if she biked the whole way:
13(x+y) = 117
13x + 13y = 117
;
Subtract the 1st equation from the above equation,
13x + 13y = 117
13x + 5y = 93
------------------subtraction eliminates x
0x + 8y = 24
y =
y = 3 hrs she walked
:
:
Find x and check solutions:
13x + 5(3) = 93
13x = 93 - 15
13x = 78
x =
x = 6 hrs on the bike
:
Using the biking for 9 hrs, check solution
13 * 9 - 117 mi
