Question

    If 1306x is divisible by 9, then find the value of

    √(x2 – 28).
    A 7 Correct Answer Incorrect Answer
    B 8 Correct Answer Incorrect Answer
    C 5 Correct Answer Incorrect Answer
    D 6 Correct Answer Incorrect Answer

    Solution

    If 1306x is divisible by 9, then sum of the digit must be divisible by 9
    So, 1 + 3 + 0 + 6 + x = (10 + x) = 9n (where n is a positive integer)
    So, (10 + x) = 18
    So, x = 18 – 10 = 8
    √(x2 – 28) = √(64 – 28) = √36 = 6

    Practice Next

    Relevant for Exams: