The accompanying table shows the weights, in pounds,

for the students in an algebra class.

Using the data, complete the cumulative frequency table

and construct a cumulative frequency histogram on the grid below.

1)

Standard DeviationStandard deviation is a measure that shows how much variation from the mean there is in a data set.The symbol is:

If the standard deviation is small, the data points are close to the mean. If it is large, then the data points are spread out.

Normal Curve Standard Deviation

𝒙mean

2) On a math Regents Exam 5,000 students took the test. The mean was 82 the standard deviation was 4.

𝒙𝟖𝟐 𝟖𝟔 𝟗𝟎 𝟗𝟒𝟕𝟖𝟕𝟒𝟕𝟎

3) For the following set of data:

65, 82, 81, 70, 93, 78, 81, 60, 98, 88

a) Find the mean and median using your calculator and then find the mode and range.

𝜎 𝑥

Standard Deviation in The Calculator

mean

standard deviation

3) For the following set of data:

65, 82, 81, 70, 93, 78, 81, 60, 98, 88

b) How many scores fall within one standard deviation of the mean?

4) For the following set of data:  

29, 35, 24, 25, 21, 21, 18, 28, 21, 26, 26, 22

a) Find the mean and median using your calculator.   

b) How many scores fall within two standard deviations of the mean?

5) For the following set of data:  

20, 13, 10, 6, 13, 10, 13, 11, 11, 10

a) Find the mean and median using your calculator.   

b) How many scores fall within one standard deviation of the mean?

6) For the following set of data:  

a) Find the mean and median using your calculator.   

b) How many scores fall within two standard deviations of the mean?

x Frequency20 322 425 427 228 2

7) For the following set of data:  

a) Find the mean and median using your calculator.   

b) How many scores fall within one standard deviation of the mean?

x Frequency80 284 487 591 395 1

Homework

Standard Deviation

Homework