Name_________________________________

Date: ____________

What is data? Data can be classified as qualitative or quantitative.

Qualitative Data Quantitative Data

Classify the following variables as qualitative or quantitative. Put a check mark next to the examples that are qualitative, and an “x” next to the examples that are quantitative.

______ a) the number of brothers a person has

______ b) the colors of lollipops in a bag

______ c) the time children spend brushing their teeth each day

______ d) the height of trees in a garden

______ e) the brand of car a person drives

______ f) the most popular holiday destinations

______ g) the amount of water a person drinks each day

______ h) the average temperatures of various cities

______ i) the items students ate for breakfast before coming to school

______ j) The amount of money that I have in my pocket.

______ k) What grade you are in (9th, 10th, 11th, 12th)

Let’s Recall: Let’s make a list of everyone’s shoe size in the class:

How can we find the mean shoe size in the class?

How can we find the median of our data?

How can we find the mode of our data?

Lesson 2-1: Intro to Descriptive Stats Learning Goals:

1. How can we classify and describe sets of data? 2. What are the measures of central tendency and how do we find them? 3. What are the measures of spread and how do we find them?

Measures of Central Tendency

Terms: Definitions:

Mean

Median

Mode

Measures of Spread

Terms: Definitions:

Range

Standard Deviation

Which of the following graphs has a larger standard deviation?

How do we calculate these values?!

1. Press

2. Select

3. Fill in

4. Go Back to STAT

5. Select

6. Option 1: 1 Var Stat

7. Type in L1 in the proper location

**Don’t forget to clear your L1 first!** What do all of these symbols mean?

�̅�

sx

σx

N

minX

Q1

Med

Q3

maxX

What doesn’t the calculator tell us?!

Let’s double check our work from earlier about our class’ shoe size

Newer Calculators

Older Calculators

Practice: 1) For the set of {8, 4, 2, 10, 2, 5, 9, 12, 2, 6}

(a) calculate the mean;

(b) find the mode;

(c) find the median.

2) Find the mean, median, mode, and standard deviation of hair cut costs shown in the table.

Mean:

Median:

Mode:

Standard Deviation:

3) The weight in kilograms of 12 students in a class are as follows.

63 76 99 65 63 51 52 95 63 71 65 83

(a) State the mode.

(b) Calculate

(i) the mean weight;

(ii) the standard deviation of the weights.

Name_____________________________

Date _____________________________

Lesson 2-1: Homework

1. The age in months at which a child first starts to walk is observed for a random group of children from a town in Brazil. The results are

14.3, 11.6, 12.2, 14.0, 20.4, 13.4, 12.9, 11.7, 13.1.

(a) (i) Find the mean of the ages of these children.

(ii) Find the standard deviation of the ages of these children.

(b) Find the median age.

2. Find the mean, median mode, and standard deviation of the number of free attempts made by 12 different players in a game.

Mean:

Median:

Mode:

Standard Deviation:

Number of Free-Throw attempts made by 12 different players in a game

3

5

2

1

1

0

3

6

2

2

3. State whether these data are discrete or continuous and quantitative or qualitative.

a. The number of sweets in a packet

_______________________________________ _________________________________________

b. The heights of students in the 8th grade

_______________________________________ _________________________________________

c. The number of red cars in a parking lot

_______________________________________ _________________________________________

d. The weights of kittens

_______________________________________ _________________________________________

e. The marks obtained by grade 7 in a science test

_______________________________________ _________________________________________

f. The color that each person wore to the school dance

_______________________________________ _________________________________________

g. The number of cm of rain each day during the month of April

_______________________________________ _________________________________________

h. The number of heads when a coin is tossed 60 times

_______________________________________ _________________________________________

i. The time it takes to run a marathon

_______________________________________ _________________________________________

4. It is stated that there are 90 cookie crisps in each box. Viktoria checked 30 boxes and the numbers of

crisps in them are recorded below.

Calculate the following statistics:

a. Mean: _________________

b. Mode: _________________

c. Q1: _________________

d. Min: _________________

e. Standard Deviation: _________________