1. Addition and Subtraction with Decimals Today you will learn to: solve problems by adding and subtracting fractions. M07.A-N.1.1.1, M07.A-N.1.1.2: To apply properties of operations to add and subtract rational numbers, including real-world contexts; To represent addition and subtraction on a horizontal or vertical number line.

2. Warm-up Problem: Subtracting Decimals The average length of a humpback whale is 13.7 meters. The average length of a killer whale is 6.85 meters. How much longer is the humpback whale than the killer whale?

3. Adding and Subtracting Decimals RULE : When adding and/or subtracting decimals, be sure to align the decimal points. NOTE: If necessary, insert zeros at the end of each so that each has the same number of decimal places. 2.310 19.100 +1.882 23.292 19.100 -1.882 17.218