SOLUTION: A car travals a certian distance with a speed 50 klm/h and return with a speed of 40km/h, calculate the average?

Click here to see ALL problems on Travel Word Problems

Question 314570: A car travals a certian distance with a speed 50 klm/h and return with a speed of 40km/h, calculate the average?
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!

Start with the idea that distance equals rate times time:

This can also be expressed as

or

For the outbound leg of this trip, we would like to know the amount of time it took. So if the rate is 50 km/h, the time for leg 1 is:

Likewise, for the return trip, leg 2, where the distance is the same but the rate is 40 km/h:

Hence, the total elapsed time for the trip is

And since the total distance traveled is , we can calculate the average rate for the whole trip by:

John