Normal Probability Distributions

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

• 100
• 25
• .5
• 1

The z-score represents.....

• the amount of standard deviations a data value is above or below the mean.
• the percentile the data value is above or below the mean.
• the amount of standard deviations a data value is above or below the median.
• the percent the data value is above or below the mean.

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

• 100
• 25
• .5
• 1

Which is NOT true about the standard normal distribution?

• It is bell-shaped.
• It is unimodal.
• The mean is 0 and the standard deviation is 1.
• It is asymmetrical.

Students pass a test if they score 50% or more.

The marks of a large number of students were sampled and the mean and standard deviation were calculated as 42% and 8% respectively.

Assuming this data is normally distributed, what percentage of students pass the test? in percentage...

• 5

• 16

• 24

• 32

The ages of the population of people living in Meru area in Ipoh are Normally distributed with mean 43 and standard deviation 14

The town has a population of 5,000.

How many would you expect to be aged between 22 and 57?

You can use this Standard Normal Distribution curve:

• 1750

• 3860

• 3870

• 4330

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

Given a mean of 75 and a standard deviation of 7, what percentage of scores are between 75 and 82?

• 68%

• 81.5%

• 16%

• 34%

Given a mean of 75 and a standard deviation of 7, what percentage of scores are above 82?

• 34%

• 81.5%

• 16%

• 2.5%

Given a mean of 75 and a standard deviation of 7, what percentage of scores are between 54 and 96?

• 34%

• 99.7%

• 95%

• 2.5%