Towns A and B are 300km apart A man travels from A to B at a

Towns A and B are 300km apart. A man travels from A to B at a speed of 120km/h and a woman travels from B to A at a speed of 80km/h. The woman begins her journey 15 minutes after the man does. How far away from B will they meet?
: Let d = distance traveled by the woman (from town B) Then (300-d) = distance traveled by the man (from town A)
: Change 15 min to .25 hrs
: Write a time equation: Time = dist/speed
Man\'s travel time = woman\'s travel time + 15 min (.25 hr)
300-d/120 = d/80 + 1/4
-5d=-540 thereore d=108.
They will meet 108km away from B Is that correct?

Solution

First we need to find the time elapsed when they meet. We can then calculate the distance traveled by either party.
So let t be the time elapsed when they meet. Then they meet when the two of them together have covered 300 km:
120*t + 80*(t-.25) = 300
Solve for t then calculate the man\'s distance from A as 120*t.