Question

Mary can mow Mrs. Greenway’s lawn in 45 minutes. Mary’s little brother takes twice as long to do the same lawn. How long will it take them if they each have a mower and they work together?

Answer 1

30 minutes

Explanation:

1/45 m + 1/90 m = 1

2/9 m + 1/90 m = 1

3/90 m = 1 Multiply both sides by 90/3

90/3 x 3/90 m = 1 x 90/3

m = 90/3

m = 30

Helping in the name of Jesus.