1. Lesson 5: Adding Decimals
Name: ___________________________________ Date: ____________
Module 1: DECIMALS
Lesson 5: Adding Decimals

2. Adding Decimals
Place value can help you understand and write and compare decimal numbers.

3. Adding Decimals

4. Example: Sports Application
Adding Decimals
Example: Sports Application
What was Carly Patterson’s total for the events other than the floor exercise?
Align the decimal points.
9.70
Use zeros as placeholders.
9.30
+9.45
Add. Then place the decimal point.
28.45
Since is close to the estimate of 28, the answer is reasonable. Carly Patterson’s total for the events other than the floor exercise was

5. Adding Decimals Check It Out
What was Carly Patterson’s total for the events other than the vault exercise?
Align the decimal points.
9.700
Use zeros as placeholders.
9.700
+9.450
Add. Then place the decimal point.
28.850
Since is close to the estimate of 29, the answer is reasonable. Carly Patterson’s total for the events other than the vault exercise was

6. Using Mental Math to Add Decimals
Adding Decimals
Using Mental Math to Add Decimals
Find the sum. A
Think: = 1.
= 2.0

7. Adding Decimals Check It Out Find the sum. A. 1.6 + 0.4
= 2.0
Think: = 1.

8. Adding Decimals Helpful Hint You can place any number of zeros at the
end of a decimal number without changing
its value.
Helpful Hint

9. Student Response Systems
Adding Decimals
Student Response Systems
Identify the sum.
A. 12.8
B. 13
C. 14
D. 15.5

10. Student Response Systems
Adding Decimals
Student Response Systems
Identify the sum.
A. 27
B. 28
C. 29
D. 30

11. Student Response Systems
Adding Decimals
Student Response Systems
During a gymnastics competition, Jack scored the following points: 9.2, 7.8, and What was Jack’s total score?
A points
B points
C points
D points