To order fractions with like denominators, look at the numerators and compare them two at a time. It is helpful to write a number in a circle next to each fraction to compare them more easily.
It would probably be 4 pizzas
3√(5c)×7√(15c²)
21√(75c³)
21√(25 c² 3c)
21√(5² c² 3c)
21× 5c√(3c)
105c√(3c)
