Organising Data

Question 1

What types of data are usually organised using a frequency table

Answer 1

Qualitative data
Discrete quantitative data

Question 2

What type of data are usually organised using a grouped frequency table

Answer 2

Continuous quantitative data

Question 3

How do you work out the total number of data points from a frequency table

Answer 3

Add up the frequencies

Question 4

What is term given for a single group in a grouped frequency table

Answer 4

Class

Question 5

The range of values in each class is usually called a … …
Fill in the blanks

Answer 5

Class interval

Question 6

1.40-80 2.81-100
How would we work out the lower and upper bounds of both classses

Answer 6

Minus 0.5 from 40 to get 39.5
Add 0.5 to 80 to get 80.5
Minus 0.5 from 81 to get 80.5
Add 0.5 to 100 to get 100.5

1. 39.5≤x<80.5
2. 80.5≤x<100.5

Question 7

1. 40≤x<80
2. 81≤x<100
   How would we work out the lower and upper bound of both classes

Answer 7

The lower and upper bounds are already given to us as it is an inequality

Question 8

To find the hidden boundary between one class and another we have to
40-80 81-100

Answer 8

Find the midpoint between the upper bound of the first class and the lower bound of the second class
Boundary=80.5

Question 9

How do we find the class width of classes when they are not inequalities

40-80 81-100 101-120

Answer 9

Find the boundaries between the first,second and third classes
39.5≤x<80.5
80.5≤x<100.5
100.5≤x<120.5

The class width is now the width of each class (upper bound-lower bound)
1.41
2.20
3.20

Question 10

How do we find the midpoint in the following grouped frequency table

40-80 81-100 101-120

Answer 10

1.Find the hidden boundaries
39.5≤x<80.5
80.5≤x<100.5
100.5≤x<120.5

2. Find the mean of each upper and lower bouond to find the midpoint of each class
3. 60
4. 90.5
5. 110.5