Question 72629: Solve and show work.
At 1:00 p.m., a car leaves a city and travels north at a rate of 55 mi/h. An hour later, a second car leaves the city and travels south at a rate of 60 mi/hr. At what time will the two cars be 285 miles apart?
Answer by Edwin McCravy(20055) (Show Source):
You can put this solution on YOUR website!
At 1:00 p.m., a car leaves a city and travels north at
a rate of 55 mi/h. An hour later, a second car leaves
the city and travels south at a rate of 60 mi/hr. At
what time will the two cars be 285 miles apart?
Let the time when they meet be t hours after 1:00 p.m.,
which is the total time the first car traveled.
FIRST SECOND THEIR
CAR'S + CAR'S = DISTANCE
DISTANCE DISTANCE APART
We use DISTANCE = RATE × TIME
The first car's RATE is 55 and its TIME is t hours, so
its distance is 55t
The second car's RATE is 60 and its TIME is 1 hour less
than the first car's, or t-1. So its distance is 60(t-1)
FIRST SECOND THEIR
CAR'S + CAR'S = DISTANCE
DISTANCE DISTANCE APART
55t + 60(t - 1) = 285
Solve that and get t = 3 hours after 1:00 p.m., or 4:00 p.m.
Edwin
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