For the following frequency distribution, what is ΣX? X: 30-34, 25-29, 20-24, 15-19, 10-14; F: 1,1,3,3,2

For the following frequency distribution, what is ΣX? X: 30-34, 25-29, 20-24, 15-19, 10-14; F: 1,1,3,3,2

• A. 8
• B. 90
• C. 110
• D. Cannot be determined

Answer: (D)

Grouping data into intervals gives you frequencies for each class, but not the exact data values themselves. Without the actual numbers within each interval, you can’t determine the exact sum ΣX. You could estimate by assigning each observation the class midpoint (the representative value) and summing, which would yield an approximate ΣX of 200 here, but the problem asks for the exact sum. Since the exact values inside each class are unknown, the information provided is insufficient, so the correct choice is cannot be determined.

Grouping data into intervals gives you frequencies for each class, but not the exact data values themselves. Without the actual numbers within each interval, you can’t determine the exact sum ΣX. You could estimate by assigning each observation the class midpoint (the representative value) and summing, which would yield an approximate ΣX of 200 here, but the problem asks for the exact sum. Since the exact values inside each class are unknown, the information provided is insufficient, so the correct choice is cannot be determined.