ANFIS - linear program - reg

I solved an optimization problem(linear program) with 7 sets of costs and 3 sets of capacity parameters. I got two costs as outputs(cost1,cost2). I solved the problem with 4 types of data like large plant, medium plant, small plant, and very small plant by changing the capacities and costs. can i model my problem in ANFIS with these 4 examples as rules ( such as if cost1 is low and cost2 is medium and ....cost 7 is high the output cost1 is medium) and predict the output costs for different costs and capacities. are the 4 examples sufficient for my model or i have to provide more examples as rules in ANFIS. If i have to provide more examples, how many ( approximately) are required?