Problema Solution

A pair of kids and a pair of adults decided to compete in a three-legged race. The kids got to start 15 yards ahead of the adults, since they had shorter legs. When they were told to start, the kids hobbled forward at a rate of 2 yards per second, and the adults hobbled after them at a rate of 3 yards per second. Soon they were side-by-side. How far did the adults go?

Answer provided by our tutors

let x = seconds of the travel to reach the point where they are side-by-side


the distance from the start that the kids made in x seconds is: 2x + 15


the distance from the start that the adults made in x seconds is: 3x


at the moment, after x seconds, they were side-by-side thus


2x + 15 = 3x


by solving the equation we find


x = 15 s


lets calculate how far did the adults go:


3x = 3*15 = 45 yards


It took 15 seconds for the adults to go 45 yards and catch up to the kids.