Question

Which term in the A.P. 60, 56, 52, 48, 44, 40, ...... is the first negative term?

Answer 1

Given A.P. is 60, 56, 52, 48, 44, 40, ...

Here, a = 60, d = 56 – 60 = – 4

Let n^th term of the A.P. be the first negative term.

Then a_n < 0

We know, a_n = a + (n – 1)d

⇒ 0 > 60 + (n – 1)(– 4)

0 > 60 – 4n + 4

0 > 64 – 4n

4n > 64

n > 16

Hence, 17^th term will be the first negative term.