The following stem-and-leaf plot represents the prices in dollars of general admission tickets for the last 26
concerts at one venue. Use the data provided to find the quartiles.
Ticket Prices in Dollars
Stem Leaves
3
0
1
1
2
5
5
6
4
0
1
2
3
5
6
7
7
5
2
2
4
4
6
3
4
5
6
6
7
9
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 set.
The data set after sorting is: 30, 40, 41, 42, 45, 45, 46, 47, 50, 51, 52, 53, 54, 56, 56, 57, 59
The lower half of the data set is: 30, 40, 41, 42, 45, 45, 46, 47
The upper half of the data set is: 50, 51, 52, 53, 54, 56, 56, 57, 59
The median of the upper half is the average of the two middle numbers, which are 54 and 56.
Q3 = (54 + 56) / 2 = 55
Therefore, the third quartile (Q3) of the ticket prices is $55.