Question

Joe, working alone, takes 8 hours to mow a lawn. Sally, working alone, can mow the same lawn in 6 hours. How long does it take them together to mow the lawn (each using their own seperate mower)?

Answer 1

Answer: 3 3/7 hours

Explanation:

you need to find out how much work they can do in an hour.

let x represent the total collaborative work

1/8 + 1/6 = 1/x

3/24 + 4/24 = 1/x

7x = 24

x = 24/7 or 3 3/7 hours (in decimal form this is 3.4286)

I cannot guarantee this is correct but hope it helped