The 4th term of an A.P. is three times the first and the 7th term exceeds twice the third term by four. Find the first term and the common difference.

Explanation

To solve the problem step by step, we will use the properties of Arithmetic Progressions (A.P.).

### Step 1: Define the terms of the A.P.
Let the first term of the A.P. be \( a \) and the common difference be \( d \).

### Step 2: Write the expressions for the 4th and 7th terms
The \( n \)-th term of an A.P. is given by the formula:
\[ a_n = a + (n-1)d \]
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