Amanda can milk the cows in 2.5 hrs. while Vicky can finish it in 5 hrs. how long will it take them to milk all the cows ?

Question

whpalmer4 · Answer

Let C be the number of cows.  Amanda can milk them all in 2.5 hrs, so she does C/2.5 cows per hour.  Vicky does C/5 cows per hour.  If they are working together, they do (C/2.5 + C/5) cows per hour.  C = rate * time.  time = C / rate and the C's will cancel out — we don't actually need to know how many cows there are in this case.

So, if the rate is (C/2.5 + C/5), how many hours will it take to milk C cows?

anonymous · Answer

thanks