Question:medium
Two pipes A, B can fill a tank in 24 min and 32 min respectively. If both pipes are opened simultaneously, after how much time should B be closed so that the tank is full in 18 min?
Two pipes A, B can fill a tank in 24 min and 32 min respectively. If both pipes are opened simultaneously, after how much time should B be closed so that the tank is full in 18 min?
Show Hint
In variable-time pipe problems, keep one pipe running the full duration and treat the other for \(t\) minutes. Add their work (rate \(\times\) time) to equal 1 full tank.
Updated On: Jul 16, 2026
- 8 min
- 12 min
- 15 min
- 20 min
Show Solution
The Correct Option is A
Solution and Explanation
Step 1: A's rate is \(\dfrac{1}{24}\) tank/min and B's rate is \(\dfrac{1}{32}\) tank/min. Let B run for \(t\) minutes while A runs for the full 18 minutes.
Step 2: The total work equation is \(18\times\dfrac{1}{24}+t\times\dfrac{1}{32}=1\), i.e. \(\dfrac{3}{4}+\dfrac{t}{32}=1\).
Step 3: Solving, \(\dfrac{t}{32}=\dfrac{1}{4}\), so \(t=8\). \[ \boxed{8\ \text{minutes}} \]
Step 2: The total work equation is \(18\times\dfrac{1}{24}+t\times\dfrac{1}{32}=1\), i.e. \(\dfrac{3}{4}+\dfrac{t}{32}=1\).
Step 3: Solving, \(\dfrac{t}{32}=\dfrac{1}{4}\), so \(t=8\). \[ \boxed{8\ \text{minutes}} \]
Was this answer helpful?
0
Top Questions on Time and Work
- Rahul, Rakshita and Gurmeet, working together, would have taken more than 7 days to finish a job. On the other hand, Rahul and Gurmeet, working together would have taken less than 15 days to finish the job. However, they all worked together for 6 days, followed by Rakshita, who worked alone for 3 more days to finish the job. If Rakshita had worked alone on the job then the number of days she would have taken to finish the job, cannot be
- CAT - 2023
- Quantitative Aptitude
- Time and Work
- Gautam and Suhani, working together, can finish a job in 20 days. If Gautam does only 60% of his usual work on a day, Suhani must do 150% of her usual work on that day to exactly make up for it. Then, the number of days required by the faster worker to complete the job working alone is
- CAT - 2023
- Quantitative Aptitude
- Time and Work
- The amount of job that Amal, Sunil and Kamal can individually do in a day, are in harmonic progression. Kamal takes twice as much time as Amal to do the same amount of job. If Amal and Sunil work for 4 days and 9 days, respectively, Kamal needs to work for 16 days to finish the remaining job. Then the number of days Sunil will take to finish the job working alone, is
- CAT - 2023
- Quantitative Aptitude
- Time and Work
- The amount of job that Amal, Sunil and Kamal can individually do in a day, are in harmonic progression. Kamal takes twice as much time as Amal to do the same amount of job. If Amal and Sunil work for 4 days and 9 days, respectively, Kamal needs to work for 16 days to finish the remaining job. Then the number of days Sunil will take to finish the job working alone, is [This question was asked as TITA]
- CAT - 2023
- Quantitative Aptitude
- Time and Work
- Want to practice more? Try solving extra ecology questions todayView All Questions
Questions Asked in SNAP exam
In the following figure, the smaller triangle represents teachers; the big triangle represents politicians; circle represents graduates and rectangle represents members of Parliament. Different regions are being represented by letters of English alphabet. On the basis of the above diagram, answer the following questions: 
- SNAP - 2024
- Venn Diagrams