Multiple choice

A pipe can fill a tank in 12 hours. After half the tank is filled, three more similar pipes are opened. What is the total time to fill the tank completely? एक पाइप किसी टंकी को 6 घंटे में भर सकता है | आधी टंकी भरने के बाद, इसी प्रकार के तीन और नल खोल दिए जाते हैं | टंकी को पूरा भरने के लिए लगा कुल समय है ?

  1. 4 hours 45 minutes/4 घंटे 45 मिनट

  2. 4 hours /4 घंटे

  3. 3 hours 45 minutes/3 घंटे 45 मिनट

  4. 45 minutes/45 मिनट
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Hindi text (6 hours) contradicts the English text (12 hours). Using 6 hours: half tank fills in 3 hours by one pipe. Remaining half is filled by 4 pipes in 0.75 hours (3/4). Total time = 3 + 0.75 = 3 hours 45 minutes. When n similar pipes work together, time reduces by factor 1/n.

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