Today we will continue Unit 2 on decimals. Students appear to be comfortable with place values (which was mostly review from 4th and 5th grade). Today we focus on adding and subtracting decimals which I also expect to be a review for most all students. We will go over the steps to adding and subtracting decimals then do a partners activity that will challenge students to place the correct series of numbers together to come up with a solution
Important points for adding and subtracting decimals include....
1.) Line up the numbers so that the decimals are in a column, and add a decimal below the "equal" bar
example: 43.083 + 22.714
line up decimals
43.083
+ 22.714
65.797
2.) Add or subtract just like you would a whole number
3.) Check your answer by working problem backwards
65.797 <-----this was my answer
- 22.714 <------this number is the smaller of the 2 being added
43.083 <------this number should equal the larger of the numbers
If one number being added or subtracted has a different number of place values, we can add zeros to the end
for example: 122.81003 + 34.02
122.81003
+ 34.02000<---add 3 zeros so 34.02 becomes 34.02000. Notice the decimals are always lined up!
156.83003
