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:
base of the triangle = 12 m
Explanation:
Area of the triangle = 1/2 * base * height
We are given that:
area = 54 m^2
height = 9 m
Substitute in the equation to get the base as follows:
Area of the triangle = 1/2 * base * height
54 = 1/2 * base * 9
108 = 9*base
base = 12 m
Hope this helps :)


solve for "a", once you get "a", plug it back into either equation to get "b"