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 20th term is ` 112`.

Explanation

To solve the problem step by step, we will use the properties of an arithmetic progression (A.P.) and the given conditions.

### Step 1: Understand the given information
We know that:
- The first term \( a = 2 \)
- The sum of the first five terms \( S_1 \) is one-fourth of the sum of the next five terms \( S_2 \).

### Step 2: Write the formula for the sum of the first \( n \) terms of an A.P.
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