Question
In a school, 40% of the students are girls, and the rest
are boys. During the annual sports event, 30% of the girls and 50% of the boys took part. If the number of girls who did not participate is 420, determine the total number of students in the school.Solution
Let the total number of students in school = 100x Number of Girls = 40x Number of Boys = 60x According to question- 70% of 40x = 420 x = 420/28 x = 15 total number of students in school = 100x = 1500
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