Question 1094585: The sum of first three terms of gp is 37/8.The sum of the first 6 terms of the series is 3367/512.Find the first term and the common ratio
Answer by greenestamps(13200)   (Show Source):
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The sum of the first 3 terms is 37/8.
The sum of the first 6 terms is 3367/512.
So the sum of terms 4, 5, and 6, is
Terms 4, 5, and 6 are terms 1, 2, and 3 each multiplied by the common ratio r 3 times, so the sum of terms 4, 5, and 6 is the sum of the first three terms, multiplied by the common ratio 3 times:
So the common ratio r is 3/4.
The sum of the first three terms is
So the first term a is 2.
Answer: first term is 2; common ratio is 3/4.
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