Pipes A B and C together can fill a cistern in 12 hours All the three pipes are opened together for ...........

Quantitative Aptitude (CPO) Pipes&cistern

Pipes A, B and C together can fill a cistern in 12 hours. All the three pipes are opened together for 4 hours and then C is closed. A

and B together take 10 hours to fill the remaining part of the cistern. C alone will fill two-thirds of the cistern in:

This questions was previously asked in

SSC CPO 9th Dec 2019 Shift-2

40 hours

48 hours

60 hours

50 hours

Let's break down the problem step by step:

- A, B, and C together fill the tank in 12 hours. This means their combined rate is 1/12 per hour.

- All three work together for 4 hours. In 4 hours, they fill: 4 × (1/12) = 1/3 of the cistern.

- The remaining part is: 1 - 1/3 = 2/3 of the cistern.

- Now, only A and B work; they take 10 hours to fill the remaining 2/3, so their rate together is: (2/3) ÷ 10 = 1/15 per hour.

- The rate of C alone: (A+B+C) - (A+B) = (1/12) - (1/15) = (5-4)/60 = 1/60 per hour.

- To fill 2/3 of the cistern by C alone: (2/3) ÷ (1/60) = 2/3 × 60 = 40 hours.

- Option 1: 40 hours (Correct answer)

- Option 2: 48 hours

- Option 3: 60 hours

- Option 4: 50 hours

The correct answer is Option 1: 40 hours.

Submit Error