The measures of spread include the range, quartiles and the interquartile range, variance and standard deviation. Let's consider each one by one.
<u>Interquartile Range: </u>
Given the Data -> First Quartile = 2, Third Quartile = 5
Interquartile Range = 5 - 2 = 3
<u>Range:</u> 8 - 1 = 7
<u>Variance: </u>
We start by determining the mean,

n = number of numbers in the set
Solving for the sum of squares is a long process, so I will skip over that portion and go right into solving for the variance.

5.3
<u>Standard Deviation</u>
We take the square root of the variance,

2.3
If you are not familiar with variance and standard deviation, just leave it.
Answer:
x = 83/3.
Step-by-step explanation:
12x + 8 + 84 = 15х +9
Solving for x:
8 + 84 - 9 = 15x - 12x
83 = 3x
x = 83/3.
I believe the answer is B, Oval.
2/3(2/8 + 4/8) = 2/3(1/4 + 1/2)
2/3(3/4) = 1/2