SOLUTION: chad drove 3 times as fast as katy pedaled. I fact, chad drove 90 miles in 2 hrs less than it took katy to pedal 40 miles. How fast did each of them travel. How long did they trave

Algebra ->  Test -> SOLUTION: chad drove 3 times as fast as katy pedaled. I fact, chad drove 90 miles in 2 hrs less than it took katy to pedal 40 miles. How fast did each of them travel. How long did they trave      Log On


   

Question 328415: chad drove 3 times as fast as katy pedaled. I fact, chad drove 90 miles in 2 hrs less than it took katy to pedal 40 miles. How fast did each of them travel. How long did they travel?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
chad drove 3 times as fast as katy pedaled.
In fact, chad drove 90 miles in 2 hrs less than it took katy to pedal 40 miles.
How fast did each of them travel. How long did they travel?
:
Let s = K's speed
then
3s = C's speed
:
Write a time equation: Time = dist/speed
:
K's time - C's time = 2 hrs
40%2Fs - 90%2F%283s%29 = 2
Reduce fraction
40%2Fs - 30%2Fs = 2
10%2Fs = 2
Multiply both sides by 2
10 = 2s
s = 10%2F2
s = 5 mph is K's speed
then
2(5) = 15 mph is C's speed
:
Find the travel times
90/15 = 6 hrs
40/5 = 8 hrs
--------------
diff: 2 hrs, confirms our solutions