Find the sum of 2 + 4 + 6 + …………. + 38?

Question: Find the sum of 2 + 4 + 6 + …………. + 38?

Solution:
2 + 4 + 6 + …………. + 38
= 2(1 + 2 + 3 + …………. + 19)
Sum of first 19 natural numbers = (19 × 20)/2
= 190

∴ 2 + 4 + 6 + …………. + 38 = 2 × 190 = 380