**We will be solving Pipe & Cistern Question in the same way we solved Work & Time question by assuming number of Pens per day Trick.**

**1) Two pipes A and B can fill a tank in 20 minutes and 30 minutes respectively.**

**If both pipes are opened together, the time taken to fill the tank is:**

**a) 50 minutes**

**b) 12 minutes**

**c) 25 minutes**

**d) 15 minutes**

**Answer: 12 minutes**

**2) A tap can fill a cistern in 8 hours and another tap can empty it in 16 hours. If both the taps are open, the time taken to fill the tank will be:**

**a) 8 hours**

**b) 10 hours**

**c) 16 hours**

**d) 24 hours**

**Answer: 16 hours**

**3) Two pipes can fill a cistern separately in 10 hours and 15 hours. They can together fill the cistern in:**

**a) 6 hours**

**b) 7 hours**

**c) 8 hours**

**d) 9 hours**

**Answer: 6 hours**