Lesson 5.6 Normal Distribution Calculations Due 2/21 11:55 pm

Last updated over 1 year ago
16 questions
Note from the author:
Get out your 68-95-99.7 Rule half sheets and your packet: Lesson 5.5 & 5.6.
No statsmedic today, only the calculator and the Normal Distribution Chart.
Get out your 68-95-99.7 Rule half sheets and your packet: Lesson 5.5 & 5.6.
No statsmedic today, only the calculator and the Normal Distribution Chart.
Required
1

What does the z-score mean?
Suppose that a Normal model described student scores in a history class.
Francisco has a standardized score (z-score) of +2.5.

This means that Francisco’s score...

8

The distribution of speed follows an approximately Normal distribution with a mean of 80 mph and a standard deviation of 7.7 mph.
Use the 'show your work' section to put in the Delorean speeds under the axis for the Normal Distribution Model.
Then answer:
What speed is 2 standard deviations above the mean?
Be sure to include units 'mph' in your answer.
I will check your normal curve data values, points will be subtracted if it is not correct.

Required
1

Give the notation for the Normal model using the Delorean Speed information above.
Use the format: N(#, #)

Required
2

Using the 68-95-99.7 Rule & your half sheet:
What percent of the runs will give the Delorean a speed greater than 87.7 mph?

THEN shade in the probability area you are calculating in the 'show your work area'.
1 point is for your shading.

Required
2

Using the 68-95-99.7 Rule & your flip book:
What percent of the runs will give the Delorean a speed between 64.6 mph and 87.7 mph?

THEN Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for your shading.

Required
3
What percent of the runs will give the Delorean a speed less than 68.45 mph?
First: what is the z-score for 68.45? _______ Enter all decimal places for this one.
Use the z-score formula:


Second: answer,
what is the proportion of runs that will give the Delorean a speed less than 68.45 mph? _______ Include four places past the decimal or as a percent.

THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for your shading.
Required
5
What percent of the runs will give the Delorean a speed greater than 85 mph?
First: what is the z-score for the speed? _______
Remember to round to two places.



Second: be careful, I am asking for the percent GREATER than 85 mph, think about what you need to do, collaborate!
What is the proportion of speeds less than 85 mph? _______
Third: What do you need to do with the value to find the proportion higher?
Enter: add, subtract, multiply or divide _______

What percent of the runs will give the Delorean a speed greater than 85 mph? _______
Hint: the area to the left and the right need to add to 1.0, the total area under the curve.
THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for your shading.
Required
7
What percent of the runs will give the Delorean a speed between 70 and 95 mph?
First: what is the z-score for the speed of 70 mph? _______
Remember to round to two places.
what is the z-score for the speed of 95 mph? _______



Second: what proportion corresponds to 70 mph? _______
what proportion corresponds to 95 mph? _______

Third: answer, what will you do with the two proportions?
Hint: you want the area BETWEEN the two points, check your notes for what you need to do if you can't remember.
Enter: add, subtract, multiply or divide _______
What percent of the runs will give the Delorean a speed between 70 and 95 mph? _______
THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for shading under the curve.
Required
1

High levels of cholesterol in the blood increase the risk of heart disease.
For teenage boys, the distribution of blood cholesterol is approximately normal with
mean μ = 151.6 milligrams of cholesterol per deciliter of blood (mg/dl) and
standard deviation σ = 25 mg/dl.

What is the Normal model for this situation?
Use the format: N(#, #)

Required
3
What proportion of teen boys have cholesterol levels less than 100 mg/dl?
First: what is the z-score for 100 mg/dl? _______ Remember to round to two places.


Second: What is the proportion? _______

THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for shading under the curve.
Required
5
Cholesterol levels of 200 or higher are considered high for teenagers.
What percent of teen boys have high cholesterol?
First: what is the z-score for 200 mg/dl? _______



Second: What is the proportion to the left of the z-score? _______
What do you need to do with the value to find the proportion higher?
Enter: add, subtract, multiply or divide _______
Third: what is the proportion GREATER than 200 mg/dl? _______

THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for shading under the curve.
Required
7
Cholesterol levels between 170 mg/dl and 200 mg/dl are considered borderline high for teenagers. What percent of teen boys have borderline high cholesterol levels?
First: what is the z-score for 170 mg/dl? _______
what is the z-score for 200 mg/dl? _______


Second: What is the proportion to the left of 170? _______
What is the proportion to the left of 200? _______

Third: what will you do with the two proportions?
Enter: add, subtract, multiply or divide _______
What percent of teen boys have borderline high cholesterol levels? _______

THEN: Shade in the probability area that you are calculating in the 'show your work' area.
1 point is for shading under the curve.
Required
2
6th grade STAAR scores were tabulated for Round Rock ISD, the normal model N(1142, 110) was appropriate for the data.
What is the mean? _______
What is the standard deviation? _______
Required
1

6th grade STAAR scores were tabulated for Round Rock ISD, the normal model N(1142, 110) was appropriate for the data.
If a student scored 1040 on his STAAR test, what was his z-score?


Round your answer to three places past the decimal.

Required
2

6th grade STAAR scores were tabulated for Round Rock ISD, the normal model N(1142, 110) was appropriate for the data.
A student scored 1040 on his STAAR test, you just calculated his z-score.
What does this mean?

Required
3

Using the normal model: N(1142, 110)
Which 6th grade STAAR score is more unusual: a score of 889 or 1351?

Hint: use the z-scores to compare