A filling pipe fills 5/7th of the cistern in 35 minutes. How long will it take to fill the complete cistern ?

Options

A. 49 minutes
B. 60 minutes
C. 35 minutes
D. 40 minutes

Answer

To solve the problem, let's break it down step by step.

### Step 1: Understand the given information
We know that the filling pipe fills \( \frac{5}{7} \) of the cistern in 35 minutes.

### Step 2: Determine the time to fill the entire cistern
To find out how long it takes to fill the entire cistern, we can set up a proportion. If \( \frac{5}{7} \) of the cistern is filled in 35 minutes, we can find the time to fill the whole cistern (which we will denote as \( T \)) using the formula:

\[ T = \text{Total time} \times \frac{\text{Total volume}}{\text{Volume filled}} \]

### Step 3: Set up the equation
Since \( \frac{5}{7} \) of the cistern takes 35 minutes, we can express the time to fill the entire cistern as:

\[ T = 35 \text{ minutes} \times \frac{7}{5} \]

### Step 4: Calculate \( T \)
Now, we can calculate \( T \):

\[ T = 35 \times \frac{7}{5} \]

To simplify this, we can first divide 35 by 5:

\[ T = 7 \times 7 = 49 \text{ minutes} \]

### Conclusion
Thus, it will take 49 minutes to fill the complete cistern.

### Final Answer
The time required to fill the complete cistern is **49 minutes**.

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