Question

the 13th term of an ap is 3 and the sum of first 14 terms is 234 find the common difference and the sum of first 21 terms
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Answer 1

We are given that the 13th of an AP is 3 and the sum of first 13 terms is 234. Let the first term of an AP be denoted by a and common difference by d. Therefore, first term, a = 33 and common difference = -2.5 . = = 168 .