I am confused by this. Please help.

Here is a sample data set that appears to be nearly normal (as suggested by the histogram).

74.8	69.9	79.7	90.8	79.2	73.4	71.9
74.6	78.1	58.6	57.8	78.5	74.2	78.5
68.8	80.1	86.2	68	74.8	60.6	77.7
89	81.1	76.8	85.7	77.9	77.9	76.8
86.2	74.6	79.2	62.6	76.4	67.7	70.8
75.2	82	84	73	67	65.6	67.4
80.9	90	73	80.1	81.2	63.2	69.9
67.4	70.1	71.9	69.6	84.8	74.2	78.7
79.9	82.6	70.3	68.8	71.9	81.5	74.4
70.3	83.3	72.8	74.4	85.7	71.9	74.6

Here is the histogram:

20 15 Frequency 10 5 55 60 65 70 75 80 85 90 95 length (cm)