Shared Work Problems

Each of the problems below is a link. If you click on the problem, it will take you to a YouTube video of a full, step-by-step solution for the problem. You may try these problems as practice and use the videos to check your answer, or you can just watch the videos to see more worked-out example problems.

1. Chris can mow a lawn in 40 minutes. Zack can mow a lawn in 60 minutes. How long would it take them working together to mow the lawn?
2. Brandy, Bobby, and Bernadette are painting a fence. Working alone, Brandy could paint the fence in 4 hours, Bobby could paint the fence in 6 hours, and Bernadette could paint the fence in 12 hours. How long would it take them to paint the fence if they worked together?
3. It takes the head custodian at a school 30 minutes less time than his assistant to set up the chairs for a program in the auditorium. Working together, they can set up the chairs in 20 minutes. How long would it take each person alone to set up the chairs?
4. Working together, Sandy and Cindy can grade a set of algebra quizzes in 18 minutes. Working alone, it would take Sandy 15 minutes longer than it would take Cindy to grade a set of algebra quizzes. How long would it take each person to grade the quizzes alone?
5. One pipe can fill a pool twice as fast as a second pipe. Together, they can fill the pool in four hours. How long would it take to fill the pool if only the slower pipe is used?