Sita can finish typing a 100 page document in 9 hours, Mita in 6 hours and Rita in 12 hours. How long will they take to type a 100 page document if they work together?

Explanation

To solve the problem of how long Sita, Mita, and Rita will take to type a 100-page document together, we can follow these steps:

### Step 1: Determine the work done by each person in one hour.
- **Sita** can finish typing 100 pages in 9 hours. Therefore, in one hour, she types:
\[ \text{Pages typed by Sita in 1 hour} = \frac{100}{9} \text{ pages} \]

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