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The mean salary of 20 workers is Rs.10,250. If the salary of office superintendent is added, the mean will increase by Rs.750. Find the salary of the office superintendent.

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#### Solution

We have,

The mean salary of 20 workers is Rs.10,250.

The sum of salary of 20 workers = 10250 × 20 = Rs. 205000

Since, the mean will increase by Rs.750 if the salary of office superintendent is added

The mean salary of 21 workers including office superintendent = 10250 + 750 = Rs. 11000

The sum of salary of 21 workers including office superintendent = 11000 × 21 = Rs. 231000

So, the salary of the office superintendent = 231000 - 205000 = Rs. 26000.

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