Question

iClicker Question 2The table is the distribution of years of schooling forchildren age 11 and younger.0 1 2 3 4 50.14 0.15 0.16 0.18 0.18 0.19A.What is the average number of years of school for achild age 11 or younger?1 yearB. 2 yearsc. 2.7 yearsD. 3 years

Answer 1

The mean (or average) from a frequency distribution is computed as follows:

$\bar{x}=\frac{\Sigma f\cdot x}{\Sigma f}$

where x is the values of the variable (in this case, years of schooling) and f is the frequency for each value.

Substituting with data from the table:

$\begin{gathered} \bar{x}=\frac{0\cdot0.14+1\cdot0.15+2\cdot0.16+3\cdot0.18+4\cdot0.18+5\cdot0.19}{0.14+0.15+0.16+0.18+0.18+0.19} \\ \bar{x}=\frac{0.15+0.32+0.54+0.72+0.95}{1} \\ \bar{x}=2.7\text{ years} \end{gathered}$