According to the question,
Rajnish is older than Rajesh and Raman.
Rajnish > Rajesh, Raman..........(i)
Ramesh is older than Rajesh but younger than Rajeev.
Rajeev > Ramesh > Rajesh........(ii)
Raman is older than Rajeev.
Raman >Rajeev.......................(iii)
Combining all, we get
Rajinish > Raman > Rajeev > Ramesh > Rajesh