Question
In an exam, the average score of 300 students is 48. If
the average score of the students who passed is 60, and the average score of those who failed is 42, what is the ratio of students who passed to those who failed?Solution
ATQ,
Let the number of students who passed be βxβ. Number of students who failed = 300 β x Total marks obtained by 300 students = 300 Γ 48 Total marks of passed students = 60x Total marks of failed students = 42 Γ (300 - x) Total marks = Marks by passed + Marks by failed 300 Γ 48 = 60x + 42 Γ (300 - x) 60x + 42 Γ 300 β 42x = 300 Γ 48 18x = 300 Γ 48 β 300 Γ 42 18x = 300 Γ 6 β x = 100 Passed students = 100 Failed students = 300 β 100 = 200 Required ratio = 100:200 = 1:2
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