Normal Distribution and Percentages Quiz

The students’ scores on a standardized test with a normal distribution have a mean of 500 and a standard deviation of 40.  What percentage of the students scored between 420 and 580?

• 47.5%

• 68%

• 95%

• 99.5%

Tags

CCSS.HSS.ID.A.4

On a mathematics quiz with a normal distribution, the mean is 8.  If the standard deviation is 0.5, what is the best approximation of the percentage of grades that lie between 7 and 9?

• 95%

• 68%

• 34%

• 5%

Tags

CCSS.HSS.ID.A.4

On a standardized test, the mean was 75 and the standard deviation was 4.0.  Approximately what percentage of the scores would fall within the range 71 to 79?

• 68%

• 99%

• 34%

• 95%

Tags

CCSS.HSS.ID.A.4

Battery lifetime is normally distributed for large samples.  The mean lifetime is 500 days, and the standard deviation is 61 days.  Approximately what percentage of batteries have lifetimes longer than 561 days?

• 84%

• 16%

• 34%

• 68%

Tags

CCSS.HSS.ID.A.4

The scores on a test approximate a normal distribution with a mean score of 72 and a standard deviation of 9.  Approximately what percentage of the students taking the test received a score greater than 90?

• 2.5%

• 5%

• 10%

• 16%

Tags

CCSS.HSS.ID.A.4

Given the following table of SAT scores for a class.  What is the range of these scores?

 Score                               Frequency

 210                                       1

 370                                       5

 640                                       7

 700                                       4

 790                                       1

• 590

• 575

• 580

• 585

What is the sample standard deviation of the data in the table below? Round to the nearest tenth.

 Scores                             

 50, 60, 70, 80, 90, 100                                              

• 18.7

• 12.8

• 17.1

• 12.5

The table below displays the number of siblings of each of the 20 students in a class.

 Number of Siblings                                   Frequency

 0                                                                                2

 1                                                                               5

 2                                                                               7

 3                                                                              4

 4                                                                              2

• 3

• 5

• 1

• 2

Tags

CCSS.6.SP.B.5A

The box plot below summarizes the data for the amount of snowfall, in inches, during the winter of 2021 for 12 locations in western New York.

What is the interquartile range?

• 80

• 110

• 50

• 30

Tags

CCSS.6.SP.B.4

CCSS.HSS.ID.A.1

The table below displays the distribution of ages of the 20 students enrolled in a college class.

Which of the following gives the correct order of the mean, median and mode of the ages?

Ages                                     Frequency

 18                                                                              6

 19                                                                              5

 20                                                                              4

 21                                                                              2

22                                                                              1

23 1

30 1

• mean < mode < median

• median < mode < mean

• mode < mean < median

• mode < median < mean

Tags

CCSS.6.SP.B.5D

CCSS.HSS.ID.A.2