Vikash went to his collage from his house on his car with a unifrom speed of 60 km` h^(-1)` and returns to his house with a different speed. If the average speed of the car, for whole journey is `50 km^(h-1)` , then find the speed of his car when it travelled from college to house.

Explanation

Let the speed of the car from college to house be x km `h^(-1)`.
Average speed = `("total distance")/("total time")`
Take the distance between A and B as d.
Time taken from A to B
Time = `("distance")/("speed")=d/60=t_(1)`
Time taken from B to A `t_(2)=d/x`
Average speed = `("total distance")/("total time")=(d+d)/(t_(1)+t_(2))`
`(2d)/(d/60+d/x)=50`
`120x=3000+50x`
`70x=3000,x=42.86kmh^(-1)`