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There is an arithmetic sequence with even terms. The sum of odd and even terms is 24 and 30 respectively. If the last term exceeds 10.5 of the first term, try to find this sequence
Let the arithmetic sequence be an, and there are 2n terms in it. The sum of odd and even terms is 24 and 30 respectively. Nd = 30-24 = 6 (1) if the last term exceeds the first term 10.5, then we get a2n-a1 = (2n-1) d = 10.5 (2). Subtract (2) from (1) to get 2 * (1) - (2) = D = 1.5, and then we get n = 4
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