JEE MainMathematicsSequences and SeriesMCQ+4 / −1
Let respectively be the sum to 12 terms of 10 A.P. s whose first terms are and the common differences are respectively. Then is equal to :
- A7360
- B7220
- C7260
- D7380
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Correct answer: C
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For the -th A.P.:
- First term , where
- Common difference since the differences are
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Sum of first terms of an A.P. is
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Simplify:
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Now sum from to :
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Use Therefore,
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Hence the correct option is which is option .
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