algebra
posted by ann caples .
Sammy can complete a programming job in 8 hours if he works alone.
Marilyn can complete the same programming job in 12 hours if she works alone.
If Sammy and Marilyn work together, how many hours and minutes will they complete the job

S > 1/8 program per hr
M > 1/12 prog / hr
together 1/8 + 1/12 = 3/24+2/24 = 5/24 prog/hr
so 24/5 = 4 4/5 hr/prog
4/5 hr * 60 min/hr = 48 minutes
so
4 hours and 48 minutes 
48 hours ... due to both coming up with different ways of creating the program, meeting time to compromise both of their designs, added time to meld both their pieces together, and added time to quality check when the two pieces don't work together.