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    Question

    How many 3's are there in the following sequence? Which

    are neither preceded by 6 nor immediately followed by 9? 9, 3, 6, 6, 3, 9, 5, 9, 3, 7, 8, 9, 1, 6, 3, 9, 6, 3, 9
    A Four Correct Answer Incorrect Answer
    B Three Correct Answer Incorrect Answer
    C Two Correct Answer Incorrect Answer
    D One Correct Answer Incorrect Answer

    Solution

    The sequence is: 9, 3, 6, 6, 3, 9, 5, 9, 3, 7, 8, 9, 1, 6, 3, 9, 6, 3, 9 We need to count the 3's that are neither preceded by 6 nor immediately followed by 9. The occurrences of 3 in the sequence are at positions: • 1st position: Preceded by 9 (not counted). • 3rd position: Preceded by 6 (not counted). • 5th position: Preceded by 6, followed by 9 (not counted). • 9th position: Preceded by 9, followed by 7 (counted). • 13th position: Preceded by 1, followed by 6 (counted). Thus, there are two 3's that meet the condition. Therefore, the correct answer is (c), Two.

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