Which term of the arithmetic sequence is 3?

Here, first term, a = 24

We know that common difference, d = a₁ – a.

We know that nth term of A.P. , t_n = a + (n – 1) d.

To find the nth term, here t_n = 3

⇒ 3 = 24 + (n – 1) (-3/4)

⇒ 3 – 24 = (n – 1) (-3/4)

⇒ -21 = (n – 1) (-3/4)

⇒ -21 × = n – 1

⇒ 28 = n – 1

⇒ n = 28 + 1 = 29

∴ t₂₉ of the given A.P. is 3.