Formula: 2 Marks
Solution: 2 Marks
We shall use short-cut method by taking assumed mean (A) = 45.5
ClassesClassdi=xi−AFrequencyfidimark(xi)fi11−2015.5−302−6021−3025.5−206−12031−4035.5−1010−10041−5045.5012051−6055.51099061−7065.520714071−8075.5304120
Mean =A+∑fidi∑fi=45.5+7050
=45.5+1.4=46.9