Problema Solution

Two pipes fill a tank. When both pipes are open, the tank can be filled in 24 minuets. The larger pipe by its self can fill the tank in 20 minutes less then the smaller pipe can the fill the tank by its self. Find the time required for each pipe by its self to fill the tank.

Answer provided by our tutors

The largee one need x minutes to filled the tank so the smaller one need (x + 20)minutes

the larger one can filled the tank 1/x every minutes ,the smaller one can filled the tank 1/(x+20) every minutes

they both work need 24minutes

so 24 *1/x +24*1/(x+20) = 1

24/x +24/(x+20) = 1

[24(x+20)+24x]/x(x+20) =1

24(x+20)+24x = x(x+20)

24x + 480 +24x = x2 +20x

x2 -28x -480 = 0

(x-40)(x+12)=0

x =40 or x = -12

time must > 0

so x =40

the larger one need 40 minutes

the smaller one need 60 minutes