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    Question

    Sum of squares of three consecutive numbers is 974. Find the sum of first and third number.

    A 42 Correct Answer Incorrect Answer
    B 30 Correct Answer Incorrect Answer
    C 34 Correct Answer Incorrect Answer
    D 36 Correct Answer Incorrect Answer

    Solution

    Let the numbers be (x – 1), x and (x + 1) => (x – 1)2 + x2 + (x + 1)2 = 974 => x2 – 2x + 1 + x2 + x2 + 2x + 1 = 974 => 3x2 = 974- 2 => x2 = 972/3 => x2 = 324 => x = 18 Required sum = (18 – 1) + (18 + 1) = 36

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