Probability of a Normal Distribution

6.2:  Standard Normal Distribution (mean is 0 standard deviation is 1).  For a randomly selected subject, find the probability of a score between 1.37 and 2.42.

• 0.078
• 0.785
• 0.223
• 0.023

Tags

CCSS.HSS.ID.A.4

6.3:  Non-Standard Normal Distribution.  IQ scores are normally distributed with mean 100 and standard deviation 15.  Find the probability of randomly selecting an IQ score above 90.

• 0.683
• 0.748
• 0.715
• 0.796

6.5 CLT:  Red blood cell counts of women are normally distributed with a mean of 4.577 and a standard deviation of 0.382.  Find the probability that one randomly selected woman has a red blood cell count above 5.4.

• 0.150
• 0.0156
• 0.215
• 0.0237

Tags

CCSS.HSS.ID.A.4

6.5 CLT:  Red blood cell counts of women are normally distributed with a mean of 4.577 and a standard deviation of 0.382.  What percentage of women have red blood cell counts in the normal range from 4.2 to 5.4?

• 82.3%
• 77.8%
• 72.6%
• 68%

Tags

CCSS.HSS.ID.A.4

6.5 CLT:  Red blood cell counts of women are normally distributed with a mean of 4.577 and a standard deviation of 0.382.  If 25 women are randomly selected, find the probability that the mean of their red blood cell counts is less than 4.444.

• 0.409
• 0.0409
• 0.368
• 0.0368

6.3 z-scores: Scores on a history test have an average of 80 with a standard deviation of 6. What is the z-score for a student who earned a 75 on the test?  (Use the formula solve for z)

• -0.83
• 0.83
• -0.17
• 0.17

Tags

CCSS.HSS.ID.A.4

6.3 z-scores: The temperature is recorded at 60 airports in a region. The average temperature is 67 degrees Fahrenheit with a standard deviation of 5 degrees. Given a z-score of -0.2, what is the temperature? (Use formula, solve for x) 

• 65
• 68
• 67
• 66

The average number of calories in a 1.5-ounce chocolate bar is 225.  Suppose that the distribution of calories is approximately normal with a σ of 10.  Find the probability that a randomly selected chocolate bar will have between 200 and 220 calories. 

• 0.9876
• 0.3023
• 0.0098
• 0.3320

Toyota Camry: Breaking distance on a wet surface is normally distributed with a mean of 149 ft. and a standard deviation of 5.28 ft. Find the probability that the randomly picked Toyota Camry will have a breaking distance more than 160 feet.

• 0.4559
• 0.0186
• 0.2244
• 2.3