Fill pipe P is 21 times faster than fill pipe Q. If Q can fill a cistern in…

2024

Fill pipe P is 21 times faster than fill pipe Q. If Q can fill a cistern in 110minutes, find the time it takes to fill the cistern when both fill pipes are opened together.

  1. A.

    5 minutes

  2. B.

    4 minutes

  3. C.

    3 minutes

  4. D.

    6 minutes

Attempted by 1 students.

Show answer & explanation

Correct answer: A

Step-by-Step Analysis
Calculate Individual Rates:

Pipe Q: Fills the cistern in 110 minutes. Its rate is 1/110 cistern per minute.

Pipe P: Fills the cistern 21 times faster than Pipe Q. Its rate is 21 * (1/110) = 21/110 cistern per minute.

Calculate Combined Rate:

Combined Rate = Rate of P + Rate of Q

Combined Rate = 21/110 + 1/110 = 22/110 cistern per minute.

Find Total Time:

Total Time = 1 / Combined Rate

Total Time = 1 / (22/110) = 110 / 22 = 5 minutes.

Explore the full course: Uptet Paper 2