Unit 6 - Normal Distribution Mini Assessment

From this histogram, the average salary is $42,050 with a standard deviation of $5,273. Which method below should you use to find the probability of a salary greater than $47,323?

• Empirical Rule calculation

• Normal Distribution calculation

• Binomial Distribution calculation

• Probability Distribution calculation

At Stats High School, students’ unweighted GPAs are normally distributed with a mean of 3.9 and standard deviation of 0.3. What percentage of students at the high school have a GPA between 3.9 and 4.5?

• 47.5%

• 16%

• 68%

• 13.5%

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CCSS.HSS.ID.A.4

A 16-ounce can of Bubbly water has a mean volume of 16 oz, with a standard deviation of 0.25 oz. Pranav opens a can and finds he has less than 15.5 oz of water. What’s the probability of this occurring?

• 0.282

• 0.0228

• 0.9772

• 0.375

Tags

CCSS.HSS.ID.A.4

The weights of beetles follow a Normal Distribution with a mean of 80 grams and standard deviation of 2g. Point C on this curve corresponds to

• 84g

• 78g

• 76g

• 80g

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CCSS.HSS.ID.A.4

The weights of beetles follow a Normal Distribution with mean 80 grams and standard deviation of 2g. About what percent of beetles have weights between 76g and 82g?

• 68%

• 95%

• 81.5%

• 47.5%

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CCSS.HSS.ID.A.4

The weights of beetles follow a Normal Distribution with mean 80 grams and standard deviation of 2g. How many beetle should we expect to weigh over 83g out of the 100 randomly selected beetles?

• 6

• 5

• 8

• Cannot be determined

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CCSS.HSS.ID.A.4

Brittany’s teacher tells her that she did well on the Statistics test; her z-score was 1.80 on the test. If the mean score on the test was a 75 with a standard deviation of 10, find Brittany’s score.

Give an example of when it would be in your favor to have a negative z-score. (Check all that apply.)

• SAT Score

• Years of experience

• Cross Country Running time

• Miles on a used vehicle

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CCSS.HSS.ID.A.4

Tim and Faith both work for Country Music Company. Tim's mean concert earnings are $180,000 and the standard deviation is $3200. Faith's mean earnings are $170,000 with a standard deviation of $12,000. Assuming both pay scales are normally distributed, who has a better probability of making between $170,000 and $180,000?

• Tim

• Faith

• Same probability

• Not enough information to answer

Tags

CCSS.HSS.ID.A.4

Select all the true statements.

• It is possible to get a z-score of 1.2 points.

• Two standard deviations below the mean is the same as a z-score of -2.

• A Normal distribution's z-score of 0 equals the median.

• There is no such thing as a z-score of -4.