Two cars are travelling from the same starting point in the same direction, having started their commute at the same time. The first car travels at a steady rate of 55 mph, while the second travels at a steady rate of 52 mph. How much time will pass before the cars are 15 miles away from each other?  Answers:
A) 3 hours B) 5 hours C) 6 hours D) 4 hours E) 7 hours
Relative Speed: 55-52= 
<gadget id="calculator">55-52</gadget>
<output>3</output>
3 mph   Distance:15 miles   Time: distance/speed=15/3= 
<gadget id="calculator">15/3</gadget>
<output>5</output>
5 hours   Correct answer is 5 hours
<result>B</result>
Two cars are travelling from the same starting point in the same direction, having started their commute at the same time. The first car travels at a steady rate of 55 mph, while the second travels at a steady rate of 52 mph. How much time will pass before the cars are 15 miles away from each other?