A leak in the bottom of a tank can empty the full tank in $8$ hours. An inlet pipe fills water at the rate of $6$ liters a minute. When the tank is full, the inlet is opened and due to the leak, the tank is empty in $12$ hours. How many liters does the cistern hold ?

A) 7980

B) 7860

C) 8640

D) 8340


A large tanker can be filled by two pipes $X$ and $Y$ in $60$ minutes and $40$ minutes respectively. How many minutes will it take to fill the tanker from empty state if $Y$ is used for half the time and $X$ and $Y$ fill it together for the other half?

A) 15 min.

B) 20 min.

C) 27.5 min

D) 30 min.


Two pipes $A$ and $B$ can fill a tank in $6$ hours and $14$ hours respectively. If they are opened on alternative hours and if pipe $A$ is opened first, in how many hours, the tank shall be full ?

A) 4

B) $4\frac{1}{2}$

C) 5

D) $5\frac{1}{2}$


Three pipes X, Y and Z can fill a tank in $6$ hours. After working at it together for $2$ hours, $Z$ is closed and $X$ and $Y$ can fill the remaining part in $7$ hours. The number of hours taken by $Z$ alone to fill the tank is:

A) 10

B) 12

C) 14

D) 16


$12$ buckets of water fill a tank when the capacity of each tank is $13.5$ liters. How many buckets will be needed to fill the same tank, if the capacity of each bucket is $9$ liters ?

A) 8

B) 15

C) 16

D) 18