The following table shows the number of children in each house of a society.Number of Children (xi​)Number of Houses (fi​)0411321735What is the average number of children per house?

To compute the average number of children per house, we apply the weighted mean formula:
$$\text{Average}=\frac{\sum (f_i\cdot x_i)}{\sum f_i}$$
Let's compute the elements:Total number of houses ($\sum f_i$):
$$\sum f_i=4+13+17+5=39$$
Total number of children ($\sum f_i\cdot x_i$):
$$\sum f_i\cdot x_i=(0\times 4)+(1\times 13)+(2\times 17)+(3\times 5)$$
$$\sum f_i\cdot x_i=0+13+34+15=62$$
Now calculate the average:
$$\text{Average}=\frac{62}{39}\approx 1.5897$$
Rounding off to two decimal places gives $1.59$.