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    Question

    Evaluate (998)3 without multiplying

    directly.
    A 990419192 Correct Answer Incorrect Answer
    B 994011992 Correct Answer Incorrect Answer
    C 994101992 Correct Answer Incorrect Answer
    D 990499192 Correct Answer Incorrect Answer

    Solution

    (998)3 = (1000 – 2)3 By using (a – b)3 = a3 – b3 – 3ab(a – b) Here a = 1000 & b = 2 (998)3 = (1000 – 2)3 = 1000000000 – 8 – (3 x 2 x 1000 x 998) = 1000000000 – 8 – 5988000 = 994011992

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