We have an universal set W of 1119 tourists

    and its subsets


M of 274 tourists;

L of 276 tourists;

U of 300 tourists;


   their in-pairs intersections

ML of 94 tourists;

MU of 79 tourists

LU of 96 tourists


    and finally their triple intersection

MLU of 26 tourists.


Based on this info, we can easily find the number of tourists who visited at least one of the three parks

    n(M U L U U) = m(M) + n(L) + n(U) - n(M ∩ L) - n(M ∩ U) - n(L ∩ U) + n(M ∩ L ∩ U) = 

                   274 + 276 + 300 - 94 - 79 - 96 + 26 = 607.


Then the number of surveyed tourists who had not visited any of these three theme parks is the COMPLEMENT

                   1119 - 607 = 512.     ANSWER