Question
In a class, 3/7 of the students are girls and rest are
boys. If 1/3 of the girls and 1/5 of the boys are absent. What part of the total number of students are present?Solution
Let the total number of students in a class be x ∴ According to the question, Number of girls = 3/7 x and number of boys = x - 3/7 x = 4/7 x Number of girls who are absent = 1/3 × 3/7 x = x/7 and number of boys who are absent = 1/5 × 4/7 x = 4x/35 ∴ Total number of students who are present = x - x/7 - 4x/35 = (35x - 5x - 4x)/35 = 26x/35 ∴ The 26/35 part of the students are present in the class.
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