Question

Two men walk at rates of 6 miles per hour and 10 miles per hour respectively. They started from the same place walking in opposite directions. In how many hours will they be 200 miles apart?

Answer 1

50 hours
10 - 6 = 4
200 divided by 4 = 50

Answer 2

Let after t hours , the two men are 200 miles apart .

So the distance travelled by first man is

$= 6t miles$

And distance travelled by second man is

$= 10 t miles$

So the equation is

$6t + 10 t = 200 \\ 16t = 200 \\ t = \frac{200}{16} = 12.5 hours$

Therefore after 12.5 hours , they are at 200 miles apart .