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    Question

    The 8th term of a G.P is eight times of fifth term. What

    will be the first term when its 6th is 64?
    A 2 Correct Answer Incorrect Answer
    B 3 Correct Answer Incorrect Answer
    C 8 Correct Answer Incorrect Answer
    D 4 Correct Answer Incorrect Answer

    Solution

    Let first term is lsquo;arsquo; and common ratio is lsquo;rrsquo; for the given geometric sequence Here given a8 = 8 x a5 and also a6 = 64 rArr; ar8 - 1 = 8 x ar5 - 1 rArr; r7 = 8 x r4 rArr; r = 2 Now take a6 = 64 rArr; ar6-1 = 64 rArr; a25 = 64 rArr; a = 2

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