The order of the pizzas from least to greatest circumference is Mario's Pizzeria, Peter's Pizzeria, Tito's Pizzeria.
Each pizza's circumference is determined by the formula for the circumference of a circle: C = 2πr, where r is the radius of the circle. The radius of each pizza can be calculated by dividing the area of a single slice by the area of a whole circle (πr²). The area of a single slice can be calculated by dividing the total area of the pizza by the number of slices.
Given the areas of the single slices and the number of slices for each pizza, we can calculate the radius of each pizza and then its circumference. Plugging in the given values, we get the following circumferences:
Mario's Pizzeria: 37.69 inches
Tito's Pizzeria: 50.25 inches
Peter's Pizzeria: 43.97 inches
Comparing these values, we can see that Mario's Pizzeria has the smallest circumference, followed by Peter's Pizzeria and then Tito's Pizzeria. Therefore, the order of the pizzas from least to greatest circumference is Mario's Pizzeria, Peter's Pizzeria, Tito's Pizzeria.