An inefficient combination of shakes and worm pizza would be 50 shakes and 4 worm pizzas.
Producing 50 shakes and 4 worm pizzas is inefficient because it does not lie on the frontier. If they want to produce 50 shakes, they should produce 6 worm pizzas to be efficient.
Find out more on the Production Possibilities Frontier at https://brainly.com/question/24693743.