Solve Fraction Addition/Subtraction Problems Practice Test

A number line shows one whole from 0 to 1 split into 12 equal parts. A point starts at $\tfrac{11}{12}$ and moves left by $\tfrac{1}{3}$ (same whole). Fraction operations depend on understanding fraction size and equivalent fractions. How does the model support the solution (what value does the point land on)?

Two students solved this problem about the same-sized whole pan of brownies: “A pan had $\tfrac{5}{6}$ of the brownies left. Then $\tfrac{1}{4}$ of the whole pan was eaten. How much of the pan is left now?” Fraction operations depend on understanding fraction size. Student 1 found a common denominator and subtracted. Student 2 subtracted $\tfrac{1}{4}$ from $\tfrac{5}{6}$ by subtracting both numerators and denominators to get $\tfrac{4}{2}$. Which explanation shows why the correct method works?