4th term of an A. P. is equal to 3 times its first term 7th term exceeds twice the 3rd term by 1. Find the first term and the common difference.
Determine the A.P. whose 3rd term is 16 and 7th term exceeds the 5th term by 12.
The 4th term of an A.P. is 11 and the 8th term exceeds twice the 4th term by 5. Find the A.P. and the sum of first 50 terms.