The following stem-and-leaf plot represents the times in minutes required for 26 co-workers to commute to work. Use the data provided to find the quartiles.
Commute Times in Minutes
Stem Leaves
1 2 5 6 7
2 1 2 2 3 4 7
3 0 1 4 7 7 7 7 9
4 1 2 3 4 7 7 7 8
Key: 1|2=12
Step 1 of 3 : Find the second quartile.
The second quartile, also known as the median, is the middle value of a data set when it is ordered from least to greatest. Since there are 26 data points, the median is the average of the 13th and 14th values.
From the stem-and-leaf plot, the 13th and 14th values are 27 and 30. Adding them together and dividing by 2:
(27 + 30) / 2 = 57 / 2 = 28.5
Therefore, the second quartile (Q2) is 28.5 minutes.