Expert: Lynn Houston - 1/19/2011

Question
Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool together?

Answer
Jim completes 1/30 of the job per minute

Sue completes 1/45 of the job per minute

Tony does 1/90 of the job per minute

Together they can fill

(1/30) + (1/45) + (1/90) = 3/90 + 2/90 + 1/90 = 6/90 = 1/15 of the job per minute

It will take them 15 minutes working together to fill the pool.