Question

To find the mean of grouped data, which of the following is true?

• A. Sum the products of midpoints and frequencies, then divide by the total frequency.
• B. None of the above
• C. Sum the midpoints of classes, then divide by the total number in classes.
• D. Sum the frequencies and divide by the number of classes.

Answer 1

Answer: (A)

Sum the products of midpoints and frequencies, then divide by the total frequency.

Answer 2

To find the mean of grouped data, calculate the midpoint for each class interval. Multiply each midpoint by its corresponding frequency. Sum these products. Divide this sum by the total sum of frequencies. This method is represented by the formula $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$.