1. Adding Decimals 5.NBT.B.7

2. 0.37+0.210.370.21 + 85.0 Here is 0.37 + 0.21.First, let’s copy the decimals below.Then let’s align the decimals carefully …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.Let’s begin in the hundredths place – what is 7 + 1?8What is 3 tenths + 2 tenths?5 tenthsHere is the decimal point.Let’s mark it below.What is 0 + 0?0So, the sum is 0.58. Adding Decimals

3. 6.482.31+ + 97.8 Here is 6.48 + 2.31.First, let’s copy the decimals below.Then let’s align the decimals carefully …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.Let’s begin in the hundredths place – what is 8 + 1?9What is 4 tenths + 3 tenths?7 tenthsHere is the decimal point.Let’s mark it below.What is 6 + 2?It’s 8.So, the sum is 8.79. 6.482.31 Adding Decimals

4. 56.8 Here is 23.4 + 5.25.First, let’s copy the decimals below.Then let’s align the decimals carefully …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.Let’s begin in the hundredths place. There is only one digit, which is a 5.Let’s mark it below.What is 4 tenths + 2 tenths?6 tenthsHere is the decimal point.Let’s mark it below.What is 3 + 5?8So, the sum is 28.65. 23.4+ 2 And here are 2 tens...… which we can mark below. 5.25 Adding Decimals +

5. 8 52.318 17.8 Here is 52.318 + 6.4.Let’s write the first decimal below.Now let’s write the second decimal …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.Let’s begin in the thousandths place. There is only one digit, which is an 8.Let’s mark it below.In the hundredths place, there is a 1.Let’s mark it below.Here is the decimal point.Let’s mark it below.What is 2 + 6?8So, the sum is 58.718. + 5 Here are 5 tens...… which we can mark below. 6.4 52.318 6.4 What is 3 tenths + 4 tenths?7 tenths Adding Decimals +

6. 73.83 + 38.7 Here is 73.83 + 24.Let’s write the first number below.Notice that 24 is not a decimal, so there are no decimal points to line up.Instead, we will write the number here …… so that the ones places are lined up.Now, we are ready to add.In the hundredths place, there is a 3.Let’s mark it below.Here is the decimal point.Let’s mark it below.What is 3 + 4?7So, the sum is 97.83. + 9 And what is 7 + 2?9 24 73.83 24 In the tenths place, there is an 8.Let’s mark it below. Adding Decimals

7. 5 1.48 + 04.8 Here is 1.48 + 36.925.Let’s write the decimals below …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.How many thousandths are there?5How many hundredths?10Here is the decimal point.Let’s mark it below.What is 1 + 1 + 6?8So, the sum is 38.405. + 3 Here are 3 tens...… which we can mark below. 36.925 1.48 36.925 In the tenths place, what is 1 + 4 + 9?14 1 1 To show 10, let’s mark the 0 …… and regroup the 1 …… so that it still says 10.To show 14, let’s mark the 4 …… and regroup the 1 …… so that it still says 14. Adding Decimals

8. Closing Question Adding Decimals

9. 1 3.491 + 63.8 Here is 3.491 + 24.87.Let’s write the decimals below …… so that the decimal points are lined up …… and the ones places are lined up.Now, we are ready to add.How many thousandths are there?1How many hundredths?16Here is the decimal point.Let’s mark it below.What is 1 + 3 + 4?8So, the sum is 28.361. + 2 Here are 2 tens...… which we can mark below. 24.87 3.491 24.87 In the tenths place, what is 1 + 4 + 8?13 1 1 To show 16, let’s mark the 6 …… and regroup the 1 …… so that it still says 16.To show 13, let’s mark the 3 …… and regroup the 1 …… so that it still says 13. Adding Decimals