Q2 of 40 Page 210

Number of families in a village in correspondence with the number of children are given below:

Find the mean number of children per family.


Given is the frequency distribution table for ungrouped data.

We have



⇒ 11 families each have no children,


25 families each have 1 child,


And so on…


This also implies that,


Total number of children of 11 families = 0 × 11 = 0,


Total number of children of 25 families = 1 × 25 = 25,


And so on…


Mean of such ungrouped data is given by



⇒


⇒ [∵, ∑xifi = 144 & ∑fi = 84]


⇒ Mean = 1.7143


Thus, mean number of children per family is 1.7143.


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