Table : TABLE A.2
Calculating the Standard Deviation
Weight XMean Weight − Mean X − (Weight − Mean) Squared (X − )2
                      155124  31           961
                      149124  25           625
                      142124  18           324
                      138124  14           196
                      134124  10           100
                      131124    7             49
                      127124    3               9
                      125124    1               1
                      120124  −4             16
                      115124  −9             81
                      112124−12           144
                      110124−14           196
                      105124−19           361
                      102124−22           484
                        95124−29           841
Sum (Σ) = 1,860 Σ = 0  Σ = 4,388
Mean () = 124