IB Math Studies Yr 1

Name_________________________________

Date: ____________

Warm-Up: 1. An IB Math Studies student, Matt, has the following test scores for the first quarter:

84, 98, 79, 82, 93 Matt wants to make sure that he gets an average of 86 for the quarter, with one more test to go. What score must Matt receive on the last test of the quarter in order to earn an average of 86?

Frequency Table:

Let’s revisit our shoe size example:

-The classroom sample of shoe size is displayed below

- Write out the 5 number summary for our class’ shoe size:

- Create a box plot to display the above information:

Shoe Size Frequency

Lesson 2-5: Frequency Tables

Learning Goals:

#5: What is a frequency table, and how do we construct/interpret frequency tables?

IB Math Studies Yr 1

- Now let’s try to create a Frequency table for our data above!

What information can we gather from frequency tables?

The numbers of games played in each set of a tennis tournament were...

9, 7, 8, 11, 9, 6, 10, 8, 12, 6, 8, 13, 7, 9,10, 9, 10, 11,12, 8, 7, 13, 10, 7, 7

The raw data has been organized in the frequency table below.

a) Write down the value of x.

b) What is the modal number of games?

c) Calculate the mean number of games played per set.

d) Write down the standard deviation of the games played per set.

Calculator Steps... Working with Frequency Tables

1) Enter your data into L1 and your frequency list in L2

2) STAT, CALC, 1-Var- Stats L1, L2

Variable List Frequency List

Don’t forget

L2 for your

frequency

list

IB Math Studies Yr 1

Frequency Tables with Intervals What is a mid-interval? How do I calculate a mid-interval?

The accompanying table shows the weights, in pounds, of a modified football team.

a) What is the modal interval for student weights?

b) What is the mid-interval of the modal interval?

c) Write down an estimate for the mean weight.

d) Calculate an estimate for the standard deviation for the weights.

Putting it all together...

For her IB Math Project, Samantha wanted to study plants. She took a random sample of six month old tulip seedlings from a nursery and measures their heights to the nearest mm.

a) What is the modal interval for tulip seedlings?

b) Write down an estimate for the mean tulip seedlings.

c) Calculate an estimate for the standard deviation for the tulip seedlings.

IB Math Studies Yr 1

Practice:

1) A survey was conducted of the number of bedrooms in 208 randomly chosen houses. The results are shown in the following table.

Number of bedrooms

1 2 3 4 5 6

Number of houses 41 60 52 32 15 8

a) Write down the mean number of bedrooms per house.

b) Write down the standard deviation of the number of bedrooms per house.

c) What is the modal value for number of bedrooms?

2) For his IB Math project Josh measures the heights of students in his class. The frequency table displays his information.

(a) Calculate an estimate for the mean height.

(b) Interpret the mean.

(c) Write down an estimate of the standard deviation of the heights.

(d) What is the modal interval for the student heights?

IB Math Studies Yr 1

Name_____________________________

Date _____________________________

Lesson 2-5: Homework

1. Below is the length of 100 books. Using the table below, calculate the

following characteristics:

a. Find the modal length of the books.

b. What is the average length of the 100 books?

c. Calculate the 5 number summary for the data above.

d. Calculate the IQR of the above data.

2. Below is the height of 59 newborn babies. Using the table, calculate the following statistics.

a. What is the mid-interval of the modal class?

b. Calculate the mean, and standard deviation of the heights of the babies.

c. Calculate the range, and interquartile range of the data.

IB Math Studies Yr 1 3. The numbers of games played in matches at a badminton tournament are recorded below.

a. Write down the values of m and n.

b. What is the mean number of games played?

c. Calculate the standard deviation.

d. Calculate the following statistics and interpret them.

Value Interpretation in a sentence

Minimum

Lower Quartile

Median

Upper Quartile

Max

IB Math Studies Yr 1

4. The following six integers are arranged from smallest to largest

1 , x , 3 , y , 14 , z

The mode is 1 , the median is 5 and the mean is 7.

a. Find x ;

b. Find y;

c. Find z.

5. Two groups of 40 students were asked how many books they have read in the last two months. The results for the

first group are shown in the following table:

The quartiles for these results are 3 and 5.

a. Write down the value of the median for these results.

b. Draw a box and whisker diagram for these results on the following grid.