Alex and Jack work for a computer software company. Alex can write a computer program in 24 hours while Jack can write it in 16 hours. How long will it take them to write the program together?

Question

anonymous · Answer

If in 1 hour, Alex does 1/24 of job, Jack does 1/16 of job
then in x hours, 
So x/16+x/24= 1 
Then multiply both by 48 
so you get 3x+2x=48... 
Solve for x and get x=9.6 hours

anonymous · Answer

Thank you so much! I understand now.

anonymous · Answer

anytime. :)