Missouri Learning Standards
MO.4.NF. Number Sense and Operations in Fractions
4.NF.B. Extend understanding of operations on whole numbers to fraction operations.
4.NF.B.4. Understand addition and subtraction of fractions as joining/composing and separating/decomposing parts referring to the same whole.
4.NF.B.6. Solve problems involving adding and subtracting fractions and mixed numbers with like denominators.