Find the sum of first 12 even natural numbers.

First 12 even natural numbers: 2, 4, 6, 8, 10, …………(up to 12 terms)

The sum of the first n even natural numbers is given by:

S = n(n+1)

where n is the number of even numbers.

Here, n = 12, so the sum is:

S = 12(12+1) = 12 × 13 = 156

Thus, the sum of the first 12 even natural numbers is 156.