College

Select the correct answer.

What is the median of this data set?

[tex]$21, 42, 63, 84, 105, 126, 147$[/tex]

A. 21
B. 63
C. 84
D. 126

Answer :

To find the median of the given data set, we need to follow these steps:

1. Order the data set: First, ensure that the data is in numerical order from smallest to largest. For this data set:
[tex]\(21, 42, 63, 84, 105, 126, 147\)[/tex], the numbers are already sorted.

2. Determine the number of data points: Count how many numbers are in the data set. In this case, there are 7 numbers.

3. Find the median:
- Since the number of data points (7) is odd, the median is the middle number in the ordered list.
- The middle position can be found using the formula:
[tex]\((n + 1) / 2\)[/tex], where [tex]\(n\)[/tex] is the number of data points.
- For this data set:
[tex]\((7 + 1) / 2 = 4\)[/tex]
- So, the median is the 4th number in the ordered list.

4. Locate the median: In the ordered list, the 4th number is 84.

Therefore, the median of the data set is [tex]\( \boxed{84} \)[/tex].