Percentage Problem

[razakazmii]

Following is the question:

In a class, 20% of the students were absent for an exam. 30% failed by 20 marks and 10% just passed. Find the average score of the class if the remaining students scored average of 65 marks and pass marks is 40?

P.s. I googled this particular problem and found the answer, but I did not the find the procedure of solving it.

 

[MarkFL]

I would use a weighted average:

[MATH]\overline{x}=0.2\cdot0+0.3\cdot20+0.1\cdot40+0.4\cdot65=36[/MATH]
I am assuming the absent students were given a score of 0 marks. Is this the answer you found by googling?

 

[Denis]

https://studysite.org/Discuss/Question/in_a_class_20_of_the_students_were_absent_for_an_exam_30_failed_by_20_marks_and_10_just_passed_find_the_average_score_of_the_class_if_the_remaining_students_scored_an_average_of_65_marks_and_the_cut_off_for_passing_the_exam_is_40-30216082.htm