posted by christy
Sue can shovel snow from her driveway in 35 minutes. Bill can do the same job in 50 minutes. How long will it take Sue and Bill to shovel the driveway if they worked together.
(1/35) + (1/50) T
T=1 (1/35) + (1/50)=
Is the answer: 21.25
exactly right, you add the rates.