Step 1 :This is a linear programming problem. We need to minimize the cost function subject to certain constraints. The cost function is \(c = 3000x + 3000y\) where \(x\) is the number of Pomegranate computers and \(y\) is the number of iZac computers.
Step 2 :The constraints are \(400x + 300y \geq 48000\) (for memory) and \(80x + 100y \geq 12800\) (for disk space). We also have the constraints \(x \geq 0\) and \(y \geq 0\) since we can't buy negative number of computers.
Step 3 :We can solve this problem using linear programming methods.
Step 4 :The result from the calculation shows that the school should buy 60 Pomegranate computers and 80 iZac computers. The minimum cost is $420,000.
Step 5 :Final Answer: The school should buy \(\boxed{60}\) Pomegranate computers and \(\boxed{80}\) iZac computers. The minimum cost is \(\boxed{420,000}\) dollars.