New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    The number of students in class IX and class X is 70 and

    75, respectively. The ratio of the number of boys to girls in classes IX and X is 9: 5 and 8: 7, respectively. What is the difference between the total number of boys and the total number of girls in both the classes taken together?
    A 25 Correct Answer Incorrect Answer
    B 15 Correct Answer Incorrect Answer
    C 20 Correct Answer Incorrect Answer
    D 28 Correct Answer Incorrect Answer

    Solution

    Number of boys in class IX = 70 × (9/14) = 45 Number of girls in class IX = 70 × (5/14) = 25 Again, Number of boys in class X = 75 × (8/15) = 40 Number of girls in class X = 75 × (7/15) = 35 Total of boys in two classes = 45 + 40 = 85 Total of girls in two classes = 25 + 35 = 60 Difference = 85 - 60 = 25

    Practice Next

    Relevant for Exams: