Question

Which term of the A.P. 53, 48, 43,… is the first negative term?

Answer 1

Let nth term is the first negative term of the A.P. 53, 48, 43, …

Here, a = 53, d = 48 – 53 = -5

∴ T_n = a + (n – 1)d

= 53 + (n – 1)  (-5)

= 53 – 5n + 5

= 58 – 5n

5n = 58

n = `(58)/(5)`

= `11(3)/(5)`

∴ 12^th term will be negative.