The shape of the distribution, is symmetric, is the best description of statistics about scores.
<h3 /><h3>What is standard deviation ?</h3>
The standard deviation is the positive square root of the variance of this data set. Variance of a data set is the sum of squared differences of the data values from its mean to the total count of data values.
The given data in the problem is;
Mean = 78%
Standard deviation = 4%
Min = 64
Median = 78
Q1 = 72
Q3 = 84
Max = 99
The condition for the symmetric distribution is found as;

From the data we have;

So that ,
.
Hence, the condition of symmetry is followed.
To learn more about the symmetry, refer to the link;l
brainly.com/question/15970176
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Let W and L be width and length of the rectangular pen respectively.
Therefore,
Circumference, C = 2W+2L= 130 yd
Area, A = LW = 1050 yd^2=> L = 1050/W
Using the circumference expression and substituting for L;
130 = 2W + 2(1050/W) = 2W+2100/W
130*W = 2W*W + 2100
130W = 2W^2 +2100
2W^2-130W+2100 = 0
Solving for W;
W= [-(-130)+/- Sqrt ((-130)^2-4(2)(2100)]/2*2 = 32.5+/- 2.5
W = 30 or 35 yd
When W = 30, L = 1050/30 = 35
When W = 35, L = 1050/35 = 30
Therefore, W = 30 yd and L = 35 yd.
1.3x10^-2 = .013
.013 x .05 = .00065
.00065 = 6.5x10^-4