A car and a bus set out at 2pm from the same point headed in the same direction the average speed of the ca r is 30 mph slower than twice the speed of the bus. In two hours, the car is 20 miles ahead of the bus what is the speed of the car?
What i have done:
Suppose the speed of the bus is x. Then the speed of the car will be 2x-30.
We need to find speed so speed=Distance/Time.
Please help me after that as i am not able to proceed further.
The options are a)40mph b)50mph c)60mph d)70mph
Let speed of bus be S (You have this as x)
Then speed of car = 2S – 30 (You have this as 2x – 30)
In 2 hours, the bus has traveled a distance of: 2S
In 2 hours, the car has traveled a distance of: 2(2S – 30), or 4S – 60
Therefore, we get: 2S + 20 = 4S – 60
2S – 4S = - 60 – 20
– 2S = - 80
S, or speed of bus = , or 40 mph
Speed of car: 2(40) – 30, or 80 – 30, or mph (CHOICE b)