Question 350001
Bob can do the job in 5 hours
so he does 1/5 of the job in 1 hour.
..
Jim does in 3 hours.
he does 1/3 of the job in 1 hour.
Together they do 1/3 + 1/5 of the job in 1 hour
=8/15 of the job.
so they will take 15/8 hours to do the job together.
1.87 hours