Thread: Time & Distance Problem

It is 165 miles from city x to city y. If a bus takes 1.5 hours to travel the first 65 miles, how long must the bus take to travel the final 100 miles in order to average 50 miles/hr during the entire trip?

what have you done so far? show your work..

if the bus has an avg speed of 50 miles per hr, then it would travel 165 miles in (165/50)= 3.3 hours....

Based on this and the information you have in your question, calculate the time taken by the bus to travel the final 100 miles.

I've done like this:

The entire trip is 165 miles.

Therefore, expected time = 165/50 * 60 minutes = 198 minutes.

The 1st 65 miles were traveled in 1.5 hrs. = 90 minutes.

So, the remaining 100 miles has to be traveled in (198-90) minutes = 108 minutes.

Therefore the answer is 108 minutes.

Is this correct? I've confusion about my book's answer, it says 115.47 minutes!

Yes.

You can check your answer..

The total time taken for the bus to travel =90+108= 198 mins = 3.3 hrs..

total distance = 165 miles..

speed = 165/3.3 = 50 miles per hr..