If xi‘s are the mid points of the class intervals of grouped data, f’is are the corresponding frequencies and x is the mean, then Σfi(xi – x̄) is equal to:
A. zero
B. – 1
C. 1
D. 2
Answer:A
If xi‘s are the mid points of the class intervals of grouped data, f’is are the corresponding frequencies and x is the mean, then Σfi(xi – x̄) is equal to:
A. zero B. – 1 C. 1 D. 2