ANSWER

Step-by-step explanation
From the given table;
Recall that mean is calculated using;
![\begin{gathered} x=\frac{\sum_^fx}{\operatorname{\sum}_^x} \\ \end{gathered}]()
The summation of frequency and the number of families is;

The summation of the frequency is;

Applying the formula; Mean;

The mean is 11.3 to one decimal place.