lisa can shovel snow from her driveway in 40 minutes jim can do the same job in 50 minutes how long would it take lisa and jim to shovel the driveway together?

Answer 1

lisa's rate = 1/40
jim's rate = 1/50
combined rate = 1/40 + 1/50 = 9/200

time for job = 1/(9/200) = 200/9 or 22 2/9 or appr. 22.22 minutes