Evaluate $2.5+\left(-8.1\right)$2.5+(−8.1).
Evaluate $-8.3+8.9$−8.3+8.9.
Evaluate $5.4+\left(-7.8\right)$5.4+(−7.8).
Evaluate $-7.2+3.3$−7.2+3.3.
Apply and extend previous understandings of operations with fractions to operations with rational numbers.
Apply properties of operations to add and subtract rational numbers, including real-world contexts.
Represent addition and subtraction on a horizontal or vertical number line.
Apply properties of operations to multiply and divide rational numbers, including real-world contexts; demonstrate that the decimal form of a rational number terminates or eventually repeats.