26th 11th And Last Terms Of Ap Are 0 3 And 1 6 Respectively

The 26th, 11th and the last terms of an AP are, 0,3 and -1/6, respectively. Find the common difference and the number of terms.

Answers:

Let the first term, common difference and number of terms of an AP are a, d and n, respectively.
We know that, if last term of an AP is known, then