Question

Bob can load his truck in 24 min. It takes his brother John 40 min to load the truck. How long it take them to do the job together?

Answer 1

1/24 - Bob load his truck in 1 min

1/40- John load the truck in 1 min 

1/24+1/40= 5/120+3/120=8/120=1/15 - Bob and John load the truck together in 1 min 

So it takes 15 minutes to do the job together.

Answer: 15 minutes