posted by moon .
A contract employs three types- Class A , Class B and class c. to class A workers, he pays an average monthly salary of $ 400, to class B workers, he pays an average monthly salary of $ 320 and to class C workers he pays an average monthly salary of $ 150. The combined average salary paid by the contractor is $ 225. If the number of class A and class B is 10 each. find the number of class C workers!
B) the standard deviaton of class A , class B and Class C workers is 15, 7 and 12 respectively. calculate the cofficient of variation of class A, B and class C workers.
c) comment on the variability in the salaries of the class A, B and C workers