Warm-up Please put your homework in the orange basket Preston was collecting coins. He got 7 coins from his piggy bank and 2 coins from his brother. His father gave Preston 12 coins. Preston gave 14 of the coins to his friend Cara. How many coins did Preston have left?
Monday, September 19, 2016 Warm-up Please copy your homework into your assignment book. Adding and Subtracting Decimals Practice Homework: Adding and Subtracting Decimals Worksheet Quiz: Wednesday Test: Rational Numbers (Fractions and Decimals) Monday
Adding and Subtracting Decimals
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
You can add a zero to help keep everything lined up 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 15.85
Add a zero to line up everything 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. 22.44
Add a zero to line up everything -8.33 + -10.972 -8.33 -10.972 Line up the decimal Add a zero to line up everything + Same signs Add – keep the sign -19.302
Subtracting Examples: 5.34 -2.08 5.34 -2.08 3.26 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
-38.59 – (-7.81) -38.59 + 7.81 -30.78 + Line up the decimal + 7.81 Line up the decimal + -30.78 Subtract to add when negatives are used. Different signs take difference
Add zeros to line up everything, then subtract 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 8 9
Independent Practice When instructed to do so, grab a purple pre-algebra book Complete: pg. 176 #’s 14-25 You will turn this in before you leave class today.