The frequency distribution of marks of 100 candidates in a particular examination is as follows: Marks | Number of Candidates More than 10 | 100 More than 20 | 75 More than 30 | 60 More than 40 | 40 What are the (average marks of the candidates?
- A. 20.5
- B. 22.5
- C. 30.5
- D. 32.5 ✓
Correct Answer: D. 32.5
Explanation
Converting the 'more than' cumulative frequencies to class intervals gives frequencies: 10-20 (25), 20-30 (15), 30-40 (20), 40-50 (40). Average marks = (15*25 + 25*15 + 35*20 + 45*40) / 100 = 3250 / 100 = 32.5.
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