Question

The following stem-and-leaf plot represents the test scores for 22 students in a class on their most recent test. Use the data provided to find the quartiles.

Test Scores by Student
Stem Leaves
6 1 6 6 6
7 1 3 4
8 1 1 5 5 7 8 8 9
9 1 3 3 3 7 7 7
Key: 6||1=61

Step 1 of 3 : Find the second quartile.

Answer 1

Using the median concept, it is found that the second quartile is of 86.

What is the median of a data-set?

The median of the data-set separates the bottom half from the upper half, that is, it is the 50th percentile. The median is also called the second quartile, as $\frac{2}{4} \times 100 = 50$.

In this problem, there are 22 scores, which is an even number, hence the median is the mean of the 11th and the 12th scores.

From the stem-and-leaf plot, we have that:

• The 1st score, in an increasing way, is 61.

• The 2nd, 3rd and 4th is 66.

• The 11th score is 85.

• The 12th score is 87.

Then:

(85 + 87)/2 = 86

The second quartile is of 86.

You can learn more about the median concept at https://brainly.com/question/25215461