Question
The marks scored by a boy in three subjects are in the
ratio 3 : 4 : 5. Boy scored an overall aggregate of 60% in the exam. If the maximum marks in each subject are the same, in how many subjects did boy score more than 75% marks?Solution
Let the maximum marks in each subject be 100. ∴ Total score = 60% of (100 + 100 + 100) = 60% of (300) = 180 Also, 75% marks in a subject correspond to 75% of (100) = 75 Let a boy have scored 3x, 4x and 5x in the three subjects. ∴ 3x + 4x + 5x = 180 ∴ 12x = 180 i.e. x = 15 Hence, his marks in the three subjects are 45, 60 and 75. Hence, he has scored more than 75 in exactly no subject.
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