Which term of the AP 53, 48, 43, … is the first negative term?


Given AP is 53, 48, 43, ….


Whose, first term, a = 53


common difference, d = 48 – 53 = - 5


Let nth term of the AP be the first negative term.


Then, we have to find the least value for which


an < 0


a + (n - 1)d < 0


53 + (n - 1) (- 5) < 0


53 - 5(n - 1) < 0


5(n - 1) > 53





so n will be least natural number greater than


i.e., 12th term is the first negative term of the given AP.


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