SOLUTION: i need the formula for this problem a car leaves Rockford, Illinois, at the rate of 65 mph, bound for Madison, Wisconsin. At the same time, a truck leaves Madison at the rate of 55

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Question 907938: i need the formula for this problem a car leaves Rockford, Illinois, at the rate of 65 mph, bound for Madison, Wisconsin. At the same time, a truck leaves Madison at the rate of 55 mph, bound for Rockford. If the two cities are 72 miles apart, how long will it take the car and truck to meet?
Found 2 solutions by josgarithmetic, stanbon:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The vehicles are approaching each other at 65+55=120 mph.
120%2At=72

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
i need the formula for this problem a car leaves Rockford, Illinois, at the rate of 65 mph, bound for Madison, Wisconsin. At the same time, a truck leaves Madison at the rate of 55 mph, bound for Rockford. If the two cities are 72 miles apart, how long will it take the car and truck to meet?
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Time for the car and the truck must be the same.
time = distance/rate
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Equation:
Let "x" be the car's distance; then 72-x is the truck's distance
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time = time
x/65 = (72-x)/55
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55x = 65(72-x)
55x = 65*72 - 65x
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120x = 65*72
x = 39 miles (car's distance)
72-x = 33 miles (truck's distance
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Ans: time = x/65 = 39/65 = 0.6 hrs = 0.6*60 = 36 minutes
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Cheers,
Stan H.
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