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A plane can fly 560 miles in the same time as it takes a car to go 240 miles. If the car travels 80 mph slower than the plane, find the speed ( in mph) of the plane.

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A plane can fly 560 miles in the same time as it takes a car to go 240 miles. If the car travels 80 mph slower than the plane, find the speed ( in mph) of the plane.​

Let

x -----> speed of the car

y -----> speed of the plane

we have that

x=y-80 -----> equation 1

Remember that

the speed is equal to divide the distance by the time

speed=d/t

t=d/speed

car -------> t=d/x -----> t=240/x

plane ----> t=560/y

equate both times

240/x=560/y

substitute equation 1

240/(y-80)=560/y

solve for y

240y=560(y-80)

240y=560y-44,800

560y-240y=44,800

320y=44,800

y=140

x=140-80=60

therefore

speed of the car is 60 mph

speed of the plane is 80 mph

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