Question
In a class, 60% of the students are boys, and the rest
are girls. If 40% of the boys and 50% of the girls passed an exam, what percentage of the total students failed the exam?Solution
Let total students in class = 100x Boys = 60x Girls = 40x passed boys = 40% of 60x = 24x passed girls = 50% of 40x = 20x total passed students = 20x+24x = 44x total failed students = 100x – 44x = 56x failed percentage of total students = 56x/100x × 100 = 56%
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