Which term of the arithmetic progression will be72 more than its 41th term?

a = 8, d = 6,

Last term = an


an= a + (n – 1) d


= 8 + (n – 1) 6


= 2 + 6n (i)


Let, 41st term, a41 = 8 + (41 – 1) 6


= 8 + 40 * 6 = 248


Now the term is 72 more than its 41st term


an = 72 + a41


= 72 + 248 = 320


Putting this value in (i), we get


320 = 2 + 6n


6n = 318


n = 53


Hence, 53rd term of the given A.P. is 72 more than its 41st term


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