Q44 of 202 Page 9

In an A.P., the first term is 2, the last term is 29 and the sum of the terms is 155. Find the common difference of the A.P.

Given, First term, a = 2

Last term, an = l = 29


And, Sum of terms, Sn = [a + l]


155 = [2 + 29]


155 * 2 = n * 31


n = = = 10


We know, an = a + (n – 1) d


29 = 2 = (10 -1) d


29 – 2 = 9d


27 = 9d


d = 3


Hence, common difference, d = 3


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