PLEASE CAN SOMEONE HELP ME WITH Q(ii)… I got 19.7 as a mean but the MS says 39.6??

Frances used the pre-release data set to produce the following table which shows information about the
residents of Norwich in 2011.

Age
0 to 15
16 to 24
25 to 44
45 to 64

Number of
residents
21707
22921
40894
27645
19345
Total: 132512
(i) State the upper class boundary of the "25 to 44" class.
[1]
Frances used these data to calculate estimates of the mean and standard deviation of the ages of these
residents. She assumed that the oldest resident was aged 105.
(ii) Calculate these estimates.
[3]