A bathtub will fill in 15 minutes with both faucets open and the stopper in place. With both faucets closed and the stopper removed, the tub will empty in 20 minutes. How long will it take for the tub to fill if both faucets are open and the stopper is removed?

Question

anonymous · Answer

45mins?

anonymous · Answer

45 min is correct

anonymous · Answer

i had thought 60 mins..

anonymous · Answer

since in 1 min, 1/15 (or 4/60) of the tub is filled and 1/20 (or 3/60) of  the tub is emptied... then 4/60-3/60 = 1/60. in one min, 1/60 of the tub will be filled and the tub will be fully filled in 60 mins...

anonymous · Answer

you have 5 extra min every time the bathtub fills up before its compleatly drained, sine it normally takes 15min, you need the 5min 3 times to make it, and in turn it you have to multiply the 15 by it as well, making 45min.

anonymous · Answer

i think u should look at how much the tub is filled in one min, cuz the faucets are opened and stopper is removed simultaneously...

anonymous · Answer

i dont know, i would say 45, 60 could be right. im confused now lol

anonymous · Answer

me too...

anonymous · Answer

p.s. on a seprate note, can you help me in history again?

anonymous · Answer

i m not too sure.. will check.. meanwhile, do u wanna check this website? there is a calculation error for it but i think my answer is right... i kinda copied the entire question n searched for it on google http://www.algebra.com/algebra/homework/Human-and-algebraic-language/Human-and-algebraic-language.faq.question.25891.html

anonymous · Answer

your answer is more correct than theirs

anonymous · Answer

haha thanx:)

anonymous · Answer

Thank you jay123 & s-jiwani