The sum of 40 terms of an AP whose first term is 4 and common

The sum of 40 terms of an AP whose first term is 4 and common difference is 4, will be —

Given that , In A.P. , first term a = 4 and common difference r = 4 , n = 40
Using the given formula ,

S₄₀ =	n	[2a + (n - 1)d]
	2

S₄₀ = 20 [4 + 39 × 4]
∴ S₄₀ = 20 × 160 = 3200