Subject Category > Mathematics

Q. The average marks obtained by 120 students in an exam is 35. If the average marks obtained by successful students is 39 and the average marks obtained by unsuccessful students is 15 then what is the number of successful students?

A) 80

B) 110

C) 100

D) 90

✔ 100

Additional Information > Exam point of View

Let the number of successful students be x. The equation is 39x + 15(120 - x) = 35 × 120. Solving for x, we get x = 90. Thus, there are 90 successful students.

Asked Question

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