SOLUTION: at 1:00 p.m., a car leave a city and travels north at a rate of 55mi/h. An hour later, a second care leaves the city and travels south at a rate of 60 mi/hr. At what time will th

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: at 1:00 p.m., a car leave a city and travels north at a rate of 55mi/h. An hour later, a second care leaves the city and travels south at a rate of 60 mi/hr. At what time will th      Log On

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Question 79115: at 1:00 p.m., a car leave a city and travels north at a rate of 55mi/h. An hour later, a second care leaves the city and travels south at a rate of 60 mi/hr. At what time will the two cars be 285 miles apart?
Found 2 solutions by checkley75, josmiceli:
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
55T+60(T-1)=285
55T+60T-60=285
115T=285+60
115T=345
T=345/115
T=3 HOURS AFTER THE FIRST CAR LEAVES THEY WILL BE 285 MILES APART.
PROOF:
55*3+60*2=285
165+120=285
285=285

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The way to read this is that the sum of the distances the cars travel
is 285 mi.
I'd like to start them both off at the same time, so the 2nd car has gone
d+=+60%2A1
d+=+60 mi when the 1st car begins to move.
d%5B1%5D+%2B+d%5B2%5D+=+55%2At%5B1%5D+%2B+60+%2B+60%2At%5B2%5D
They travel for the same amount of time now, so
t%5B1%5D+=+t%5B2%5D
285+=+55t+%2B+60+%2B+60t
115t+%2B+60+=+285
115t+=+225
t+=+45%2F23 hrs
The time will be 1 pm + 1 hr + 45/23 hrs
This is 1 pm + 3 hrs - 1/23 hrs, or
4 pm - 1/23*60 min, or
3 pm + 57.4 min
I hope I didn't make a mistake