The mean monthly salary paid to 77 employees in a company was Rs. 78. The mean salary of 32 of then was Rs. 45 and of the other 25 was Rs. 82. What was the mean salary of the remaining ?

The mean monthly salary paid to 77 employees in a company was Rs. 78.

1.	The mean monthly salary paid to 77 employees in a company was Rs. 78. The mean salary of 32 of then was Rs. 45 and of the other 25 was Rs. 82. What was the mean salary of the remaining ?
Answer» Solution :`"Given: "N=77,barX_(123)=78""N_(1)=32,barX_(1)=45` `N_(2)=25,barX_(2)=82""N_(3)=77-32-25=20` USING theformula of combined arithmetic mean, we have `barX_(123)=(barX_(1)N_(1)+barX_(2)N_(2)+barX_(3)N_(3))/(N_(1)+N_(2)+N_(3))` `78=(45xx32+82xx25+barX_(3)xx20)/77` `78=(1,440+2,050+20barX_(3))/77` `78=(3,490+20barX_(3))/77` `3,490+20barX_(3)=6,006` `20barX_(3)=6,006-3,490` `20barX_(3)=2,516` `barX_(3)=(2,516)/20=125.8` Mean SALARY of the remaining EMPLOYEES = Rs `125.8`.