In an A.P. the first term is 2 and the sum of the first five terms is one fourth of the next five terms. Show that `20^(th)` term is -112.

Explanation

To solve the problem, we need to find the 20th term of an arithmetic progression (A.P.) where the first term \( a = 2 \) and the sum of the first five terms is one fourth of the sum of the next five terms.

### Step-by-Step Solution:

1. **Identify the first term and the common difference**:
- Let the first term \( a = 2 \).
- Let the common difference be \( d \).

...