1. Adding and Subtracting Decimals Math Unit 1

2. O Adding and subtracting decimals requires you to add like terms. O 5.NBT.7

3. Learning Goal O B.E.L., We will add and subtract decimals.

4. 4 APK O Decimal: A number that uses place value and a decimal point to show tenths, hundredths, and thousandths. O 0.1 is a decimal number for one tenth. O 0.12 is a decimal for twelve hundredths. O 0.125 is a decimal for one hundred twenty-five thousandths. O Decimal point: A period separating the ones and the tenths in a decimal. O 2.7 O Equivalent Decimals: Decimals that name the same number. O 0.3 and 0.30 are equivalent decimals.

5. 5 APK O Example: O Three hundred forty-four thousandths OnesTenths Hundredths 0.3 4 Thousandths 4 0.344

6. 6 APK – Comparing/Ordering Decimals O Use place value O Step 1 O Line up the decimal points. Compare the ones. 5.7 5.9 O Step 2 O Compare the tenths 5.7 5.9 Think: 5 = 5 Think: 7 < 9 5.7 < 5.9

7. 7 Let’s Try One O Order 5.49, 5.4, 5.57, and 6.03 from greatest to least

8. Adding/Subtracting Decimals O 1. Line up the decimal points O 2. Add or subtract like you normally would. O 3. Bring the decimal straight down into your answer.

9. I Do: 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.

10. 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

11. We Do: 8.33 + 10.972 8.33 10.972 Add a zero to line up everythin g 0 Line up the decimal 19.302 +

12. Your Turn Add 0.36 + 0.46

13. I Do: 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

14. We Do: 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

15. Your Turn O Find the difference; 0.9 – 0.2

16. 1.3.082 + 16.4 + 6.422. 5.62 – 1.8 3.0.54 + 2.8 + 24 + 3.0174. 17 – 1.834 5. 17.93 – 8