Ans : Mean of grouped data , if x1 ,x2 ,x3 ,........ ,xn are n value of variable X then
Mean =( x1 + x2 + x3 + ........ + xn ) / n Median = if n is odd ,then median is the value of [ ( n+1) /2]th observation , if n is even , then median is the AM of the value of ( n/2) th and [(n/2) +1 ]th observation
If a variable X takes value x1 , x2 , x3 ,........ ,xn with corresponding frequencies f1 , f2 , f3 ,...... fn respectively
Mean = (f1*x1 + f2*x2 + f3*x3 + ......+fn* xn) / (f1 + f2 +.........+fn)
Mode: = 3 Median - 2 Mean
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