Pipes A,B and C are fitted to a tank .Each of A and B and can fill a tank in 9 hours. C is an emptying pipe which can empty it in 12 hours. It is fitted aton-third the height of the tankabove the in which the tank will be filled(in hours).

Pipes A,B and C are fitted to a tank .Each of A and B and can fill a t

1.	Pipes A,B and C are fitted to a tank .Each of A and B and can fill a tank in 9 hours. C is an emptying pipe which can empty it in 12 hours. It is fitted aton-third the height of the tankabove the in which the tank will be filled(in hours).
Answer» 5 `5(1)/(2)` `6.3` `6(1)/(2)` Solution :Each of A and B can FILL the bottom one-third of the tan in `(1)/(3)(9)` hours=3 Time in which it will be FILLED `((3)(3))/(3+3)"hours"=(3)/(2) "hours"=1(1)/(2)` hours Part of the top two-thrid of the tank which A,B anc C can fill each HOUR `=(1)/((2)/(3))((1)/(9)+(1)/(9)+(1)/(12))=(1)/(6)+(1)/(6)-(1)/(8)=(5)/(24)` `:.` Time in which it will be fileld `=(24)/(5)` hours. Total time in which the tank will be filed `=(3)/(2)+(24)/(5)=6.3` hours.