Question 343639
Larry starts cycling at 20 mi/hr. One hour later, Rebecca starts cycling from the same place at 25 mi/hr, going in the same direction on the same road as Larry. How long will it take Rebecca to catch up to Larry?
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This is right, this equation makes use of the fact that when R catch L then
they will have traveled the same distance.
Dist = speed * time
:
T = L's travel time. (dist = 20T)
R started 1 hour later so
(T-1) = R's travel time. dist = (25(t-1))
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With this in mind, the equation is:
L's dist = R's dist
20T = 25(T-1)
20T = 25T - 25
20T - 25T = -25
-5T = -25
T = -25/-5
T = 5 hours.
YOu solved for T correctly, you can prove this by finding the dist each has
traveled, they should be equal
L's dist: 20*5 = 100 mi
R's dist: 25(5-1) = 100 mi also
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