Question

Car A travels 120 miles in the same time that car B travels 150 miles. If car B averages 10 mph faster than car A, what is the speed of each car?

Answer 1

Speed of car A = 40 mph

Speed of car B = 50 mph

Explanation:

Given:

Distance travelled by car A = 120 miles

Distance travelled by car B = 120 miles

To Find:

speed of each car = ?

Solution:

Let the speed of car A be x

then speed of car B is (x +10)

The Time taken for each car is same

Time taken for car A = Time taken for car B

We know that time =
`(distance)/(speed)`

Time taken for car A

=>
`(120)/(x)`---------------------------(1)

Similarly

Time taken for car B

=>
`(150)/(x+10)`-----------------------(2)

Equating (1) and (2), we get

`(120)/(x)` =
`(150)/(x+10)`

`120 * (x+10) = 150 * x`

120x + 1200 = 150x

1200 = 150x-120 x

1200 = 30x

`x= (1200)/(30)`

x= 40

Speed of car A = 40mph

Speed of car B = (x+10) = (x+40) = 50mph