Chapter 2.2, Problem 11P

Harry wants to make $\frac{3}{4}$ of a recipe of a potion. The full recipe calls for 2 vials full of newt blood. Instead of calculating $\frac{3}{4}$ of 2, Harry measures $\frac{3}{4}$ of a vial of newt blood 2 times and uses this amount to make $\frac{3}{4}$ of his potion recipe. Is Harry’s method valid? Using our definition of fractions, explain why or why not.