Sorry bro, You have provided incomplete data. For accurate calculation Date of appointment and birth is required.
If he has retired after completion of at least 20 years service his Basic Pension after commutation will be Rs. 6,687/-
The calculation will be as follows:-
Basic Pension: 6,687/-
D.R:(45%)3,009/-
M.A: 300/-
Total:9,996/-
He has completed nearly 39 yrs of service..As he joined on 1973 and DOB 10/12/1951