Question
The average income of a group of 30 freelancers is Rs.
500. If 3 freelancers earning an average of Rs. 550 leave the group and 1 freelancer earning Rs. N joins the group, then the average income of the group increases by Rs. 60. Find the value of ‘N’.Solution
Total income of 30 freelancers initially = 30 × 500 = Rs. 15000 New average income of the group = 500 + 60 = Rs. 560 New number of freelancers in the group = 30 - 3 + 1 = 28 According to the question, 15000 - 3 × 550 + N = 560 × 28 Or, 15000 - 1650 + N = 15680 Or, 13350 + N = 15680 Or, N = 15680 - 13350 = 2330
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