Question

a car travels 1/2 of the distance between two cities in 3/5 of an hour .at this rate what fraction of the distance between the two cities can the car travel in 1 hour

Answer 1

Remark
The easiest way to do this is to set up a proportion. But be careful how you do it.

Call the distance d
1/2 d / 3/5 hour = x * d / 1 hour
 
Divide both sides by d
1/2 // 3/5 = x / 1    Cross multiply
1/2 * 1 = 3/5 x       divide by 3/5
$\frac{ \frac{1}{2} }{ \frac{3}{5} }$

Invert the bottom fraction and multiply.
$\frac{1}{2} * \frac{5}{3} = \frac{5}{6}$       
The answer is 5/6 of the distance will be covered in 1 hour.

Answer 2

By proportion this is  1/2 *  1 / 3/5  = 1/2 * 5/3 =  5/6 of the distance.