This document contains data with two columns of numbers labeled X and f. There are 6 data points listed with values for X ranging from 4 to 9 and corresponding f values. The document also contains calculations of the mean (Mx) of X which is 6.2, and the standard deviation (SD) of X which is 1.44 based on this data.

1. Data:
X f
4 5
5 9
6 10
7 8
8 5
9 3
X f fX X-Mx (X-Mx)2
f(X-Mx)2
4 5 20 -2.2 4.84 24.20
5 9 45 -1.2 1.44 12.96
6 10 60 -0.2 0.04 0.40
7 8 56 0.8 0.64 5.12
8 5 40 1.8 3.24 16.20
9 3 27 2.8 7.84 23.52
40 248 82.40
2.06
Mx 6.2
SD 1.44