Write the class mark of the class `19.5 - 29.5`.

Answer

To find the class mark of the class interval `19.5 - 29.5`, we can follow these steps:

### Step 1: Identify the lower and upper limits
- The lower limit of the class is `19.5`.
- The upper limit of the class is `29.5`.

### Step 2: Use the formula for class mark
The formula to calculate the class mark (also known as the midpoint) is:
\[ \text{Class Mark} = \frac{\text{Lower Limit} + \text{Upper Limit}}{2} \]

### Step 3: Substitute the values into the formula
Substituting the lower and upper limits into the formula:
\[ \text{Class Mark} = \frac{19.5 + 29.5}{2} \]

### Step 4: Calculate the sum of the limits
Now, calculate the sum of `19.5` and `29.5`:
\[ 19.5 + 29.5 = 49 \]

### Step 5: Divide the sum by 2
Now, divide the sum by `2` to find the class mark:
\[ \text{Class Mark} = \frac{49}{2} = 24.5 \]

### Final Answer
Thus, the class mark of the class `19.5 - 29.5` is **24.5**.

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