Interpreting graphs
Looking at the column graphs which colour is the most popular?
Yellow
The entire group being looked at
What is the mode?
Most often
What is an outlier?
A number that's a lot bigger or a lot smaller
Draw the stem and leaf plots for this set of data: 30, 31, 30, 34, 25, 28, 42, 55, 48
Draw on whiteboard
Looking at the column graph what flavour/s is more popular for males than females?
Strawberry and Vanilla
What is a sample?
A subset of the population
How do you calculate the mean?
Add all the numbers up and then divide by how many numbers there are
How do you find the range?
Biggest number - smallest number
Draw the Stem and leaf plot for: 2.3, 4.5, 3,7, 2.4, 2.3, 3.6
Draw on whiteboard
Looking at the line graph what is the most popular day for donuts?
Friday
You are trying to find the average amount of siblings people have and you just ask your friends. What are the positives and negatives of this?
Positive: Easy
Negative: not a good representation
Find the median of these numbers: 3, 5, 4, 8, 9
5
Find the range: 3, 6, 2, 7, 8
8 - 2 = 6
Looking at the back to back stem and leaf plot did shop A or shop B have more sales?
Shop A
Looking at the line graph what is the minimum amount of donuts sold in one day?
4 boxes
If the population is students at Dromana College what would be a representative sample?
eg. 10 people from each year level
Can there be more than one mode?
yes
Find the range of this data: 22, 30, 12, 32, 28, 29
32 - 12 = 20
What does the vertical axis on a histogram show?
Frequency
Which type of graph is best used for continuous data?
Line graph
What is a random stratified sample?
A sampling method where a population is divided into groups and people are chosen at random from each group.
What is the mean: 10, 6, 8, 12
9
If there is an outlier what measure of centre does it affect the most?
Mean
What is wrong with these histogram intervals? 140-149, 150-159, 160-179, 180 - 189
they are not even