Q98.The average marks of boys in a class is 52 and that of girls is 42 . The average marks of boys and girls combined is 50 . The percentage of boys in the class is (1) 40 (2) 20 (3) 80 (4) 60
What This Question Tests
This question is a straightforward application of the weighted average formula to calculate the combined mean of two groups (boys and girls) and determine the percentage of one group in the total.
Concepts Tested
Formulas Used
Combined mean = (n1*avg1 + n2*avg2) / (n1 + n2)
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean (Average)
- Year
- 2007
- Shift
- Unknown
- Q Number
- Q98
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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