Question

College roommates John and David were driving home to the same town for the holidays. John drove 55 mph, and David, who left an hour later, drove 60 mph. How long will it take for David to catch up to John?

a) 2 hours
b) 2.5 hours
c) 3 hours
d) 3.5 hours

Answer 1

It will take David 3 hours to catch up to John.

Step-by-step explanation:

To find the time it takes for David to catch up to John, we can set up an equation using the formula: distance = speed x time. Let's assume t is the time it takes for David to catch up to John. From John's perspective, his distance traveled is 55t. From David's perspective, his distance traveled is 60(t-1) since he left an hour later. Since they both meet at the same point, their distances traveled should be equal. Setting up the equation, we get 55t = 60(t-1). Solving this equation, we find that t = 3 hours. So, it will take David 3 hours to catch up to John.