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For the series S = 1 + 1 1 + 3 1 + 2 2 + 1 1 + 3 + 5 1 + 2 + 3 2 + 1 1 + 3 + 5 + 7 1 + 2 + 3 + 4 2 + . . . . . , if the 7 t h term is K , then K 4 is equal to

Correct answer

4

Step-by-step solution

r t h term, T r = 1 + 2 + 3 + . … … . . + r 2 1 + 3 + 5 + . … … . . + 2 r - 1 = r r + 1 2 2 r 2 = r + 1 2 4 T 7 = 8 2 4 = 64 4 = 16 K 4 = 16 4 = 4

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