Maths-
General
Easy
Question
In a geometric progression, if the ratio of the sum of first 5 terms to the sum of their reciprocals is 49, and the sum of the first and third terms is 35, then the first term of this geometric progression is
- 7
- 21
- 28
- 42
The correct answer is: 28
Let the sum of first 5 terms of the GP be
Now according to question
Let a = 7. Now
Thus, first term is
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