On Stability in Fuzzy Linear Programming Problems ∗ Robert Full´ er rfuller@ra.abo.fi, http://www.abo.fi/˜rfuller/robert.html Abstract This study focuses on the problem of stability (with respect to changes of centres of fuzzy parameters) of the solution in Fuzzy Linear Programming (FLP) problems with symmetrical triangular fuzzy numbers and extended operations and inequalities. 1 Introduction Sensitivity analysis in FLP problems (with crisp parameters and soft constraints) was first considered in [2], where a functional relationship between changes of parameters of the right-hand side and those of the optimal value of the primal objective function was derived for almost all conceivable cases. In [3] a FLP problem (with symmetrical triangular fuzzy numbers) was formulated and the value of information was discussed via sensitivity analysis. In the present paper we in- vestigate the stability of the solution in FLP problems (with symmetrical triangular fuzzy numbers and extended operations and inequalities) with respect to changes of fuzzy param- eters. We show that the solution to these problems is stable (in metric C) under variations in the membership function of the fuzzy coefficients. 2 Preliminaries Definition 2.1. A fuzzy set of the real line given by the membership function ˜ a(t)=    1 - |a - t| α if |a - t|≤ α, 0 otherwise, (1) Where α> 0 will be called a symmetrical triangular fuzzy number with center a ∈ R and width 2α and we shall refer to it by the pair (a, α). * The final version of this paper appeared in Fuzzy Sets and Systems, 30(1989) 339-344. 1