@gananime said:Actually I had made the same mistake which you did when I was solving the mock. Later on when I analyzed it,I realized my mistake.Since we are emptying the tank in 120 minutes, the equation should be1/30 + 1/24 - 1/R = -1/120Negative sign because the volume is decreasing per minute.If we solve using this,we get the correct answer as 180 litres.
@MBAVichar said:Question 7 in this AIMCMAT..... answer given is 180i am getting it as 225they have formed the equation as Let R be time taken by third pipe to fill the tank...then they have equation as 1/R - 1/30 -1/24 = 1/120But i think as the time taken is for emptying the tank not for filling..... the equation shud be 1/30 + 1/24 - 1/R = 1/120then we get R= 15 and ans as 225your views pls..
Since we are emptying the tank in 120 minutes, the equation should be
1/30 + 1/24 - 1/R = -1/120
Negative sign because the volume is decreasing per minute.
If we solve using this,we get the correct answer as 180 litres.
Two pipes P and Q can empty a tank in 30 minutes and 24 minutes respectively. Another pipe R can fill the tank at 15 litres per minute. All the pipes were opened simultaneously. The tank was emptied in 120 minutes. Find the capacity of the tank.
@gananime said:What is your doubt?