# Two vans leave a campground at the same time. One is traveling north at a speed that is 10 mi/hr faster than the other, which is traveling south. After 2.5 hours, the vans are 255 miles apart. What is the speed iof the van traveling south?

Aug 7, 2018

The speed is $= 92 \text{ mph}$

#### Explanation:

Let the speed of the van travelling south $= v \text{ mph }$

The distance travelled by the car travelling north is

${d}_{1} = 10 \cdot 2.5 = 25$

The distance travelled by the car travelling south is

${d}_{2} = v \cdot 2.5 = 2.5 v$

The distance between the cars after $2.5 h$ is

${d}_{1} + {d}_{2} = 255$

$25 + 2.5 v = 255$

$2.5 v = 255 - 25 = 230$

$v = \frac{230}{2.5} = 92 \text{ mph}$

The speed is $= 92 \text{ mph}$