SOLUTION: The first three terms of the finite sequence 1, 1/x, 2, y form an arithmetic sequence, while the last three terms form a geometric sequence find the values of x and y.

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Question 1167377: The first three terms of the finite sequence 1, 1/x, 2, y form an arithmetic sequence, while the last three terms form a geometric sequence find the values of x and y.
Answer by ikleyn(52776) About Me  (Show Source):
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Then the term  1%2Fx  is the arithmetic mean of its neighbors


    1%2Fx = %281%2B2%29%2F2 = 3%2F2,   so  x = 2%2F3.



Hence, the terms  3%2F2, 2 and y form a geometric progression.


Then the ratio of this progression is  2%2F%28%283%2F2%29%29 = 4%2F3  and  y = 2%2A%284%2F3%29 = 8%2F3.


ANSWER.  x= 2%2F3,  y= 8%2F3.

Solved.