it takes mandy 4 hrs to put up paneling in a room. omar takes 5 hrs to do the same job. how long would it take them, working together, to panel the room?

Question

anonymous · Answer

in one hour mandy can do how much of the work???

anonymous · Answer

doesn't say.

hero · Answer

Hint: 

M = Mandy's Hours
O = Omar's Hours

$$Time = \frac{M \times O}{M + O}$$

anonymous · Answer

as he compltes the job in 4 hours 
so he will do 1/4th of the job in one hour

hero · Answer

$$Time = \frac{4 \times 5}{4 + 5}$$

anonymous · Answer

i see, thank you hero and sheg.

anonymous · Answer

similarly omar completes the job in 5 hours so he will complete 1/5th of the job in one hour

hero · Answer

By the way, when I say "Time", I mean in hours.

anonymous · Answer

got it, thanks.