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JEE Main 2002
Exam
JEE Main
Year
2002
Subject
Mathematics
Chapter
Statistics

JEE Main 2002 · Mathematics · Statistics

In a class of 100 students there are 70 boys whose average marks in...

In a class of 100 students there are 70 boys whose average marks in a subject are 75. If the average marks of the complete class is 72, then what is the average of the girls?

Options

  1. A73
  2. B65
  3. C68
  4. D74

Correct answer

B. 65

Step-by-step solution

Total student =100;=100 ; for 70 stds 75 \times 70=5250 \Rightarrow 7200-5250=1950 \text{ Average of girls }=195030=\frac{1950}{30}=65 $$
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