There are 45 male and 15 female employees in an office. If the mean salary of the 60 employees is Rs 4800 and the mean salary of the male employees is Rs 5000, then the mean salary of the female employees is

In a certain year, the average monthly income of a person was Rs.3,400. For the first eight months of the years, his average monthly income was Rs. 3,160 and for the last five months, it was Rs.4,120. His income in the eighth month of the year was: 

The average per day income of A, B and C is Rs. 450. If the average per day income of A and B be Rs. 400 and that of B and C be Rs. 430, the per day income of B is: 

The present age of a father is 3 years more than three times the age of his son. Three years hence, father's age will be 10 years more than twice the age of the son. The father's age is: 

The average weight of three men A, Band C is 84 kg. D joins them and the average weight of the four becomes 80 kg. If E whose weight is 3 kg more than that of D, replaces A, the average weight of B, C, D and E becomes 79 kg. The weight of A is: 

of the three numbers, the first is 3 times the second and the third is 5 times the first. If the average of the three numbers is 57, the difference between the largest and the smallest number is: 

Subjects, there were 9 boys and some girls. In a test, the mean score obtained by the boys was 13 while that obtained by the girls was 15. If the overall average was 14.28, what was the total number of students in the class? 

The average salary of all the staff in an office of a corporate house is Rs 5,000. The average salary of the officers is Rs 14,000 and that of the rest is Rs 4,000. If the total number of staff is 500, the number of officers is