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If the sum of the first ten terms of an ...

If the sum of the first ten terms of an `A.P` is four times the sum of its first five terms, the ratio of the first term to the common difference is:

Text Solution

Verified by Experts

The correct Answer is:
`(1)/(2)`
Let a be the first term and d be the common difference of A.P.
According to the question.
`S_(10)=4S_(5)`
`rArr5[2a+9d]=4xx5/2[2a+4d]`
`rArr10a+45d=20a+40d`
`10a-5d=0`
`rArra/d=1/2`
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