Find the 12th term from the end of A.P. -2, -4, -6, …., -100.

Here, common difference = d = -4 - (-2) = -2 and last term = l = -100.

We know that the nth term from last is given by the formula:
nth term from end = l - (n - 1)d

∴ 20th term from end = -100 - (12 - 1)(-2) = -100 - 11 × (-2) = -100 + 22 = -78.

Hence, the 12th term from last term of the A.P. -2, -4, -6, …., -100 is -78.