Multiple choice

A tap can empty a tank in 12 minutes, while second tap can empty it in 24 minutes. If both the taps are kept open, then how much time is required to empty the cistern?

  1. 24 minutes

  2. 8 minutes

  3. 36 minutes

  4. 12 minutes

  5. 18 minutes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Tap 1 empties in 12 min (rate 1/12), Tap 2 in 24 min (rate 1/24). Combined rate = 1/12 + 1/24 = 3/24 = 1/8. Time = 8 minutes.

AI explanation

Using the rate formula, the first tap empties at 1/12 of the tank per minute and the second tap empties at 1/24 of the tank per minute. Their combined emptying rate is 1/12 plus 1/24, which equals 2/24 plus 1/24, resulting in 3/24 or 1/8 of the tank per minute. Therefore, it takes 8 minutes for both taps to empty the cistern together. The answer is 8 minutes.

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