The 24th term of an A.P. exceeds its 19^th term by 10, its common difference is :

1. 5

2. 2

3. 10

4. 1

Let first term of A.P. be a and common difference be d.

By formula,

⇒ a_n = a + (n - 1)d

⇒ a₂₄ = a + (24 - 1)d = a + 23d.

⇒ a₁₉ = a + (19 - 1)d = a + 18d.

Given,

24th term exceeds 19^th term by 10.

⇒ a₂₄ - a₁₉ = 10

⇒ a + 23d - (a + 18d) = 10

⇒ a - a + 23d - 18d = 10

⇒ 5d = 10

⇒ d = $\dfrac{10}{5}$ = 2.

Hence, Option 2 is the correct option.