Question

In a dataset with values 10, 15, 20, 25, and 30, what is the median?

• A. 15
• B. 20
• C. 25
• D. 30

Hint:

Always make sure the dataset is sorted before finding the median. A common trap in exam questions is to provide an unsorted list of numbers.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
The median is the middle value in a dataset that has been arranged in numerical order (either ascending or descending).
Step 2: Key Formula or Approach
1. Sort the dataset.
2. If the number of data points (n) is odd, the median is the middle value, which is the \( \left(\frac{n+1}{2}\right) \)-th term.
3. If the number of data points (n) is even, the median is the average of the two middle values.
Step 3: Detailed Explanation
The given dataset is: \{10, 15, 20, 25, 30\}.
First, we check if the dataset is sorted. It is already in ascending order.
The number of data points, n, is 5, which is an odd number.
The position of the median is the \( \left(\frac{5+1}{2}\right) = \frac{6}{2} = 3 \)-rd term.
The 3rd term in the ordered dataset is 20.
Step 4: Final Answer
The median of the dataset is 20.