Q7 of 49 Page 112

Find the sum of first 22 terms of an AP in which and 22nd term is 149.

We have; n = 22, d = 7 and a22 = 149


We know;


an = a + (n – 1)d


Or, a = 149 – 147 = 2


The sum can be calculated as follows:




= 11*151


= 1661


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