Q1 of 46 Page 1

Which term of the A.P. 10, 7, 4, ... is – 41 ?

Here, a = 10, d = 7 – 10 = -3 and an = -41

To find: n


We have,


an = a + (n – 1)d


⇒ -41 = 10 + (n – 1) × (-3)


⇒ -41 = 10 – 3n + 3


⇒ -41 = 13 – 3n


⇒-41 – 13 = -3n


⇒ -54 = -3n


⇒ n = 18


Therefore, the 18th term of the given AP is -41.


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