Two pipes running together can fill a pipe in 11 1/9 minutes. If one pipe takes 5 mins more than the other to fill the tank separately. Find the time in which each pipe would fill the tank separately.
Let one of the pipes take x minutes to fill, then the slower pipe will take (x + 5) minutes.
Time taken by both pipe to fill the tank 
Portion of tank filled by faster pipe in 1 minute 
Portion of tank filled by faster pipe in 1 minute 
Portion of tank filled by both pipe in one 1 minute 
According to the question,
⇒ 200x + 500 = 9x2 + 45x
⇒ 9x2 + 45x – 200x – 500 = 0
⇒ 9x2 – 155x – 500 = 0
⇒ 9x2 – 180x + 25x – 500 = 0
⇒ 9x (x – 20) + 25 (x – 20) = 0
⇒ (9x + 25) (x – 20) = 0
But x can't be negative as it represents time.
∴ X = 20 minutes.
Time taken by faster pipe to fill the tank = 20 minutes.
Time taken by slower pipe to fill the tank = 20 + 5 = 25 minutes.