Question
The average salary of a group of 60 employees is Rs.
400. If 6 employees receiving an average salary of Rs. 450 leave the group and 4 new employees receiving an average salary of Rs. M join the group, then the average salary of the group increases by Rs. 50. Find the value of ‘M’.Solution
ATQ, Total salary of 60 employees initially = 60 × 400 = Rs. 24000 New average salary of the group = 400 + 50 = Rs. 450 New number of employees in the group = 60 - 6 + 4 = 58 According to the question, 24000 - 6 × 450 + 4M = 450 × 58 Or, 24000 - 2700 + 4M = 26100 Or, 21300 + 4M = 26100 Or, 4M = 26100 - 21300 = 4800 Or, M = (4800/4) = 1200
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