Illustrative Mathematics
Illustrative Mathematics: 4.nbt What's My Number?
The purpose of this task is for students to reason about base-ten numbers on the number line in a way that will require them to use what they know about place value. Students first represent addition and subtraction on the number line in...
Shmoop University
Shmoop: Fractions & Decimals: Adding & Subtracting Decimals
The mathematics notes investigate how to add and subtract decimals. Examples and practice problems with solutions are included.