Answer:
7.16.
Step-by-step explanation:
The variance is ∑ (x - m)^2 / N and the standard deviation is the square root of this.
m is the mean of the data . Here it is 82.14.
Construct a table:
x (x - m) (x - m)^2
73 -9.14 83.54
76 -6.14 37.70
79 -3.14 9.86
82 -0.14 0.02
84 1.86 3.46
84 1.86 3.46
97 14.86 220.82
Total: 358.86
Variance = 358.86 / 7 = 51.27
Standard deviation = √51.27 = 7.16.
