Question

It would take Jack $4$ hours to mow the lawn if he works alone. Fortunately, after he mows for $2$ hours, Jill joins him. They finish mowing $90$ minutes later. How many minutes would it have taken for Jill to mow the entire lawn alone?

Answer 1

Answer: 720

Step-by-step explanation:

Answer 2

1/4+1/x=1/3
1/x=4/12 3/12
1/x=1/12
12=x
It takes Jill 12 hours to mow the lawn
12 hours = 720 minutes