Incomes of employees in an industrial concern are given below. The total income of the 10 employees in the class over $ 2500 is $ 30,000.
Income (S)
Below 500
500-1000
1000-1500
1500-2000
2000-2500
2500 and over
Frequency
90
150
100
80
70
10
(a) Compute the mean income.
(b) Every employee belonging to the top 25% of the earners is required to pay 5% of his/her income to the workers' relief fund. Estimate the contribution to this fund.