Question

What is the median of this set of values: 2, 5, 7, 10, 10, 15, 20?

• A. 2
• B. 10
• C. 15
• D. 20

Hint:

With 7 values sorted, the median is the 4th value.

Answer 1

The Correct Option is B

Step 1: Recall the definition of median.
The median is the middle value of a data set once every value is arranged in increasing order.

Step 2: Arrange the data and count it.
The values given are already in increasing order:
\[ 2,\ 5,\ 7,\ 10,\ 10,\ 15,\ 20 \]
There are \(n = 7\) values in this set, an odd number.

Step 3: Find the middle position.
For an odd count \(n\), the median sits at position
\[ \frac{n+1}{2} = \frac{7+1}{2} = 4 \]
So we need the 4th value in the ordered list.

Step 4: Read off the 4th value.
Counting through the list, \(2\) is 1st, \(5\) is 2nd, \(7\) is 3rd, and \(10\) is 4th.

Final Answer:
\[ \boxed{10} \]