Question

    There are ‘x’ students in a class. Out of them

    ‘y’ are girls. The number of boys is 5 more than the number of girls. The sum of weight and the average weight of the girls is 506 kg and 46 kg, respectively. If 4 students are selected for a quiz competition then what will be the probability that the number of boys and the number of girls are equal?
    A 54/133 Correct Answer Incorrect Answer
    B 44/117 Correct Answer Incorrect Answer
    C 60/149 Correct Answer Incorrect Answer
    D 56/1615 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Total number of students = x The number of girls in the class = y The number of boys in the class = (y+5) Therefore the number of girls, => y = 506/46 = 11 Total number of girls = 11 Total number of boys = (11 + 5) = 16 Total number of students = (11 + 16) = 27 Required Probability = (11C2 × 16C2)/ 27C4 => (11 × 4)/117 = 44/117

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