Question

The formula to calculate mean (Long Method) from classified data is:

• A. \( M = \frac{\sum fN}{N} \)
• B. \( M = \frac{\sum x}{N} \)
• C. \( M = \frac{\sum fix}{\sum x} \)
• D. \( M = \frac{\sum fix}{N} \)

Hint:

In the long method of calculating the mean, multiply the frequency by the class midpoint for each class and sum them up, then divide by the total number of observations.

Answer 1

The Correct Option is D

The formula for calculating the mean (long method) from classified data is given by \( M = \frac{\sum fix}{N} \), 
where 
\( f \) represents the frequency of the class, 
\( x \) represents the mid-value of the class, and 
\( N \) is the total number of observations. 

Thus, the correct answer is (D).