This paper is concerned with four diophantine systems, namely,
(i)

,

;
(ii)

,

;
(iii)

,

;
(iv)

,

.
Parametric solutions
as well as numerical examples of solutions in positive integers of the first
three diophantine systems have been obtained in the paper. For the fourth
diophantine system, solutions do not exist in positive real numbers and a
single numerical solution in integers has been obtained.