Download Lesson 3.08 Adding Variances Example 1

Math 3
Lesson 3.08 Adding Variances
Name: ________________________
Example 1: In a game, you spin each spinner below once. Start by calculating the mean, mean
absolute deviation, variance, and standard deviation for each spinner.
Spinner 1 -
𝑥
x−x
(x − x )
Mean:
Mean Absolute Deviation:
Variance:
Standard Deviation:
Spinner 2Mean:
Mean Absolute Deviation:
Variance:
Standard Deviation:
𝑦
𝑦−𝑦
𝑦−𝑦
!
2
Now let Z be the random variable defined by the sum of the values on the two spinners. Write
out the sample space for the sum of the values.
Z (Sum of the spinners)
Mean:
Mean Absolute Deviation:
Variance:
Standard Deviation:
𝑧
𝑧−𝑧
𝑧−𝑧
!
Conclusions:
Use the chart below to summarize your results from above:
Spinner 1
Spinner 2
Z (Sum of Spinners)
Mean
Mean Absolute
Deviation
Variance
Standard Deviation
Do you notice any special relationship that exists for the mean, the variance or the standard
deviation?
Homework: Review the Example on p. 220-221 and then do p. 223-224 #2-5, 9, 11