how do we coefficient of variation in discrete series
In the discrete series you are given the items(X) along with their frequency(F). Steps required to calculate coefficient of variation.
1.Take one value from items (X) as assumed mean that is 'A' and calculate deviation dx = X-A.
2. Muliply frequency with dx then we get fdx and add all of them to get
.
3. Again multiply fdx by dx so we will have
and add all of them to get 
.
4. Now, calculate mean by A +
( N is summation of frequency 
)
5. Calculate standard deviation by
6. Cofficient of variation =
1.Take one value from items (X) as assumed mean that is 'A' and calculate deviation dx = X-A.
2. Muliply frequency with dx then we get fdx and add all of them to get
3. Again multiply fdx by dx so we will have
4. Now, calculate mean by A +
5. Calculate standard deviation by
6. Cofficient of variation =