Below is a table showing population age group projections made by the US Census Bureau for the year 2025

Age Group                               Number of People (millions)

0 to under 20……………………..……..                   94.3

20 to under 40………………………..…                   92.9

40 to under 60…………………….........                    85.0

60 to under 80…………………….……                    70.3

80 to under 100……………………..….                    14.8

100 to 120……………………..….........…….                  .1

                                                              Total = 357.4

a. Convert the frequency table to a relative frequency table.

b. Use the relative frequency table to approximate the mean, variance and standard deviation for the age data represented.