1. Adding and Subtracting Decimals

2. Essential Question: How do I add and subtract decimals? Always line up decimals Add and subtract like you always do Bring 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. 4.55 + 11.3 You can add a zero to help keep everything lined up 0 15.85 When adding or subtracting you always start from the right and work left.

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

5. -8.33 + -10.972 -8.33 -10.972 Same signs Add – keep the sign Add a zero to line up everythin g 0 Line up the decimal -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. 5.34 -2.08 3.26 Different signs Take difference

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

8. 28 – 15.911 When there is not a decimal put one behind the number. 28. -15.911 Add zeros to line up everything, then subtract 000 799 80. 219

9. 0.57 4.625 8.75 Magic Square 6.3750.57 5.254.6254 2.258.752.875 The sum of each row, column, and diagonal must be the same. Sums to 13.875