1.

10. Two pipes Pand Q can fill a cistand at the end of 3 minutes, P is closed. How much longer will the cistem take to til?ern in 12 minutes and 15 minutes respectively. Both are opened together

Answer»

In such kind of questions, take the LCM of 12,15 i.e. 60. Assume 60 ltrs is the capacity of cistern.Now, the rate of filling for pipe P- 60/12 = 5 ltrs per min.the rate of filling for pipe Q- 60/15 = 4 ltrs per min

So at the end of 3 mins, the cistern will have - 15 ltrs (From pipe P-5X3) +12 ltrs (From pipe Q-4X3) =27 ltrs

At the end of 3 mins, cistern will have remaining capacity of33 ltrs (60 ltrs- 27 ltrs)

As only pipe Q will fill the cistern = 33/4 = 8.25 mins =8 mins 15 seconds.



Discussion

No Comment Found