Question : Two pipes A and B can fill a cistern in $12 \frac{1}{2}$ hours and 25 hours, respectively. The pipes are opened simultaneously and it is found that due to a leakage in the bottom, it took 1 hour and 40 minutes more to fill the cistern. When the cistern is full, in how much time will the leak empty the cistern?
Option 1: 45 hours
Option 2: 42 hours
Option 3: 48 hours
Option 4: 50 hours
Correct Answer: 50 hours
Solution : Since pipe A can fill a cistern in $12 \frac{1}{2}$ hours So, work done by Pipe A in 1 hr = $\frac{2}{25}$ Similarly work done by B in 1 hr = $\frac{1}{25}$ ⇒ Work done by both A and B together in 1 hr = $\frac{2}{25}$ + $\frac{1}{25}$ = $\frac{3}{25}$ So, time taken by both A and B together to finish the work = $\frac{25}{3}$ hr = 8 hr 20 min With the leak total time taken = 8 hr 20 min + 1 hr 40 min = 10 hr 1 hr work of leak = 1 hr work of A and B together without leak - 1 hr work of A and B together with leak = $\frac{3}{25}$ – $\frac{1}{10}$ = $\frac{30 – 25}{250}$ = $\frac{1}{50}$ So, the leak can empty the filled cistern in 50 hours. Hence, the correct answer is 50 hours.
Result | Eligibility | Application | Selection Process | Cutoff | Admit Card | Preparation Tips
Question : Two pipes can fill a cistern in 12 hours and 16 hours, respectively. The pipes are opened simultaneously and it is found that due to leakage at the bottom, it takes 90 minutes more to fill the cistern. How much time will the leakage take to empty the filled tank?
Question : Two pipes A and B can fill a tank in 12 hours and 18 hours, respectively. Both pipes are opened simultaneously. In how much time will the empty tank be filled completely?
Question : Pipes A, B and C together can fill a cistern in 12 hours. All three pipes are opened together for 4 hours and then C is closed. A and B together take 10 hours to fill the remaining part of the cistern. C alone will fill two-thirds of the cistern in:
Question : Two inlet pipes can fill a cistern in 10 and 12 hours respectively and an outlet pipe can empty 80 gallons of water per hour. All three pipes working together can fill the empty cistern in 20 hours. What is the capacity (in gallons) of the tank?
Question : Two pipes can fill a tank in 15 hours and 4 hours, respectively, while a third pipe can empty it in 12 hours. How long (in hours) will it take to fill the empty tank if all three pipes are opened simultaneously?
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile