Question
In a class, 70% of the students
are adults, and 40% of the adults are females. If the number of adult males in the class is 105, what is the total number of students in the class?Solution
ATQ, Let total number of students in the class be '100a'. So, number of adults in the class = 100a X 0.7 = '70a' And, number of adult females in the class = 70a X 0.4 = '28x' So, number of adult males in the class = 70a - 28a = '42a' ATQ; 42a = 105 Or, a = 2.5 So, total number of students in the class = 100 × 2.5 = 250
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