Question
The average wage of a group of 25 labourers is Rs. 470.
If 4 persons receiving average wage of Rs. 350 leave the group and 2 persons receiving average wage of Rs. K join the group, then the average wage of the group increases by Rs. 46. Find the value of βKβ.Solution
Total wage of 25 labourers in the initial group = 25 Γ 470 = Rs. 11750 New average wage of the group = 470 + 46 = Rs. 516 New number of labourers in the group = 25 β 4 + 2 = 23 So, according to the question, 11750 β 4 Γ 350 + 2K = 516 Γ 23 Or, 11750 β 1400 + 2K = 11868 Or, 10350 + 2K = 11868 Or, 2K = 11868 β 10350 = 1518 Or, K = (1518/2) = 759
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