Question

The mean from the following table will be: 

• A. 24.62
• B. 26.66
• C. 28.64
• D. 30.50

Hint:

Always multiply each class frequency by its class mark and divide by the total frequency to get the mean.

Answer 1

The Correct Option is B

Step 1: Find class marks (midpoints). 
For each class, \[ x_i = \dfrac{\text{Upper limit + Lower limit}}{2} \] 

Step 2: Find $f_i x_i$ and total. 

\[ \Sigma f_i = 30, \quad \Sigma f_i x_i = 800 \] Step 3: Apply the formula for mean. 
\[ \bar{x} = \dfrac{\Sigma f_i x_i}{\Sigma f_i} = \dfrac{800}{30} = 26.66 \] Step 4: Conclusion. 
Hence, the mean = 26.66.