Adding and Subtracting Decimals

1. Adding and Subtracting Decimals

2. Math Objective:Add and subtract decimals 3 Steps for Adding and Subtracting Decimals 1. Always line up decimals to line up place values. 2. Add and subtract like you always do. 3. Bring the decimal straight down in your answers.

3. Adding Examples: 4.55 + 11.3 Put the first number on the top of the second number and line up the decimals. You can add a zero to help keep everything lined up When adding or subtracting you always start from the right and work left. 4.55 + 11.3 0 15.85

4. 6.44 + 16 When there is not a decimal put one behind the number. Line up the decimal Add a zero to line up everything 6.44 + 16. 0 22.44

5. -8.33 + -10.972 -8.33 -10.972 Line up the decimal Add a zero to line up everything 0 + Same signs Add – keep the sign -19.302

6. Subtracting Examples: 5.34 -2.08 Put the first number on the top of the second number and line up the decimals. Different signs Take difference 5.34 -2.08 3.26

7. -38.59 – (-7.81) -38.59 + 7.81 Line up the decimal + -30.78 Subtract to add when negatives are used. Different signs take difference

8. 28 – 15.911 When there is not a decimal put one behind the number. Add zeros to line up everything, then subtract 7 9 9 28. -15.911 000 . 1 2 0 8 9