Answer:
Minimum = 4
First quartile = 6.5
Median = 13.5
Third quartile = 19
Maximum = 20
Step-by-step explanation:
1. Order the data set from the smallest to the largest number:
4 4 9 9 18 18 20 20
2. Find the minimum:
The minimum of the data set is the smallest number
Minimum = 4
3. Find the maximum:
The maximum of the data set is the largest number
Maximum = 20
4. Find the median:
As the data set has an even number of data, the median is the average between 9 and 18, that are the two data in the middle:
Median =
Median = 13.5
5. Find the first quartile:
The median divide the data set between two groups:
4 4 9 9 Median=13.5 18 18 20 20
The first quartile is the average of the two data in the middle of the first group:
4 4 9 9
First quartile =
First quartile = 6.5
6. Find the third quartile:
The third quartile is the average of the two data in the middel of the second group:
18 18 20 20
Third quartile =
Third quartile = 19