Statistics Normal Probabilities Empirical Rule

95% of students at school weigh between 62 kg and 90 kg.

Assuming this data is normally distributed, what are the mean and standard deviation?

• Mean = 66 kg

  S.D. = 7 kg

• Mean = 76 kg

  S.D. = 7 kg

• Mean = 86 kg

  S.D. = 7 kg

• Mean = 76 kg

  S.D. = 14 kg

What is the the total area under the standard normal distribution curve?

• 100

• 25

• .5

• 1

What is the Normal Range (68%) of the annual precipitation for Phoenix, if the average is 29 with a standard deviation of 3?

• 26-32

• 3-29

• 26-29

• 39-32

The average waist size for teenage males is 29 inches with a standard deviation of 1.4 inch. 
If waist sizes are normally distributed, estimate the proportion of teenagers who will have waist   sizes greater than 31 inches?

• 92.4%

• 10.5%

• 16%

• 7.6%

Given a mean of 75 and a standard deviation of 7, how many students out of 500 would score higher than 68?

• 11

• 12

• 420

• 250

The distribution of heights of adult American men is approximately Normal with mean 69 inches and standard deviation 2.5 inches. What percent of men are between 64 and 66.5 inches tall? 

• 50%

• 2.5%

• 13.5%

• 34%

68% of the marks in a test are between 51 and 64

Assuming this data is normally distributed, what are the mean and standard deviation?

• Mean = 57

  S.D. = 6.5

• Mean = 57

  S.D. = 7

• Mean = 57.5

  S.D. = 6.5

• Mean = 57.5

  S.D. = 13

What is the area under the normal curve between the mean and one standard deviation to the right?

• 0.16

• 0.34

• 0.50

• 0.84

What is the area under the normal curve between the mean and one standard deviation to the left?

• 0.16

• 0.34

• 0.50

• 0.84

What is the area under the normal curve between one standard deviation to the left and one standard deviation to the right of the mean?

• 0.16

• 0.34

• 0.50

• 0.68