Nebraska Core Academic Content Standards
NE.MA.4.1. NUMBER: Students will communicate number sense concepts using multiple representations to reason, solve problems, and make connections within mathematics and across disciplines.
MA.4.1.2. Operations: Students will demonstrate the meaning of addition and subtraction of whole numbers and fractions and compute accurately.
MA.4.1.2.h. Determine the reasonableness of whole number products and quotients in real-world problems using estimation, compatible numbers, mental computations, or other strategies.