The mean monthly salary paid to 75 workers in a factory is ₹ 5680. The mean salary of 25 of them is ₹ 5400 and that of 30 others is ₹ 5700. Find the mean salary of the remaining workers.

Given,


Mean salary of 75 workers = Rs.5680


Total salary of 75 workers = 75 × 5680 = Rs.426000


Mean salary of 25 workers of them = Rs.5400


Total salary of 25 workers = 25 × 5400 = Rs.135000


Mean salary of 30 workers in them = Rs.5700


Total salary of 30 workers = 30 × 5700 = Rs.171000


Let Mean salary of remaining 20 workers = Rs. X


Total salary of 20 workers will be = Rs.20x


So, we have,


Salary of 75 workers = salary of (25 workers + 30 workers + 20 workers)


426000 = 135000 + 171000 + 20x


= 20x = 426000 – 306000 = 120000


= x =


Hence, Salary of 20 workers = Rs.6000.


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