Question

The mean of first five prime numbers is

(a) 5.6 (b) 5.5 (c) 5.4 (d) 5.2

Answer 1

The first five prime numbers are: 2, 3, 5, 7, 11.
$$\begin{gathered} \mathrm{Mean}=\frac{\mathrm{Sum}\mathrm{of}\mathrm{observations}}{\mathrm{Number}\mathrm{of}\mathrm{observations}} \\ =\frac{2+3+5+7+11}{5} \\ =\frac{28}{5} \\ =5.6 \end{gathered}$$
Thus, the mean of first five prime numbers is 5.6.
Hence, the correct option is (a).