Question 1060938: A car and a bus set out at 2 pm from the same point, headed in the same direction. The average speed of the car is 30 mph less than twice the average speed of the bus. In 2 hrs, the car is 30 miles ahead of the bus. Find the rate of the car.
Answer by ikleyn(52798)   (Show Source):
You can put this solution on YOUR website! .
A car and a bus set out at 2 pm from the same point, headed in the same direction.
The average speed of the car is 30 mph less than twice the average speed of the bus.
In 2 hrs, the car is 30 miles ahead of the bus. Find the rate of the car.
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The first equation is
C = 2B - 30, (1) where C is the car speed, B is the bus speed.
The second equation is
2C - 2B = 30. (2)
Rewrite the equations in this form
C - 2B = -30, (1')
2C - 2B = 30. (2')
Distract the equation (1') from equation (2') (both sides). You will get
2C - C = 30 - (-30),
C = 60.
So, you just found the speed of the car it is 60 mph.
From this point please complete the solution on your own.
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