SOLUTION: A car and bus set out at the same time. The average speed of the car is 30mph slower than twice the spped of the bus. In two hours, the car is 20 miles ahead of the bus. What is th

Question 238505: A car and bus set out at the same time. The average speed of the car is 30mph slower than twice the spped of the bus. In two hours, the car is 20 miles ahead of the bus. What is the rate of the car?
Found 2 solutions by nyc_function, josmiceli:
Answer by nyc_function(2741) (Show Source): You can put this solution on YOUR website!
Car's rate = 2x - 30
Car's time = 2
bus's rate = x
bus' time = 2
Your equation:
2(2x - 30) = 2x
Can you solve for x now?

Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
I can write 2 equations, 1 for each vehicle

and

---------------
given:
mi/hr
hrs
hrs
mi
---------------
Now I plug in the substitutions

(1)
and

(2)
Substitute (2) in (1)
(1)

mi/hr
and, since

mi/hr
The rate of the car is 50 mi/hr
check:

mi
and

In 2 hours, the car is 20 mi ahead of the bus
OK