SOLUTION: A car leaves town at noon traveling 40 mph. Two hours later, a second car leaves the same town, on the same road, traveling at 60 mph. At what time will the second car pass the fir

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Question 342043: A car leaves town at noon traveling 40 mph. Two hours later, a second car leaves the same town, on the same road, traveling at 60 mph. At what time will the second car pass the first car? I know the answer is 6pm, but I don't know how to get there.
Found 2 solutions by scott8148, Alan3354:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the cars pass when they have traveled the same distance
___ the faster car travels two hrs less than the slower car

40(t) = 60(t-2)

40t = 60t - 120

-20t = -120

t = 6

6 hrs after noon is 6 PM

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
In 2 hours, the 1st car is 80 miles away (40*2).
The 2nd car gains on the 1st at 20 mph (60 - 40). Or, the speed of the 2nd car relative to the first is 20 mph.
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80/20 = 4 hours to overtake.
2 PM + 4 hours = 6 PM