The weights (in kg) of 10 students of a class are given below:
21,28.5,20.5,24,25.5, 22, 27.5,28,21 and 24. Find the median of their weights.

Answer

To find the median of the weights of the 10 students, we can follow these steps:

### Step 1: List the weights
The weights of the students are:
- 21, 28.5, 20.5, 24, 25.5, 22, 27.5, 28, 21, 24

### Step 2: Arrange the weights in ascending order
To find the median, we first need to arrange the weights in ascending order:
- 20.5, 21, 21, 22, 24, 24, 25.5, 27.5, 28, 28.5

### Step 3: Determine the number of observations (n)
Count the number of weights:
- There are 10 weights (n = 10).

### Step 4: Identify if n is odd or even
Since n = 10, which is even, we will use the formula for finding the median in an even set of numbers.

### Step 5: Calculate the positions for the median
For an even number of observations, the median is the average of the n/2-th and (n/2 + 1)-th terms.
- n/2 = 10/2 = 5
- (n/2 + 1) = 5 + 1 = 6

### Step 6: Find the 5th and 6th terms
From the ordered list:
- 5th term = 24
- 6th term = 24

### Step 7: Calculate the median
Now, we find the median by averaging the 5th and 6th terms:
\[ \text{Median} = \frac{\text{5th term} + \text{6th term}}{2} = \frac{24 + 24}{2} = \frac{48}{2} = 24 \]

### Final Answer
The median of the weights is **24 kg**.

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