The following stem-and-leaf plot represents the prices in dollars of general admission tickets for the last 22
concerts at one venue. Use the data provided to find the quartiles.
Ticket Prices in Dollars
Stem Leaves
3
0
1
2
4
5
8
4
2
4
7
8
9
5
3
6
7
6
3
3
3
4
5
5
6
8
Key: 3|0=30
Step 3 of 3 : Find the third quartile.
To find the third quartile (Q3), we need to find the median of the upper half of the data.
The data in the upper half of the dataset is:
53, 55, 56, 57, 58, 64, 64, 66, 75, 89
The number of data points in the upper half is 10, which is an even number. To find the median of this upper half, we take the average of the two middle values, which are the 5th and 6th values when the data is ordered:
56, 58
The average of 56 and 58 is (56+58)/2 = 57.
Therefore, the third quartile (Q3) is 57.