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

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

Adding Decimals

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 28.45 is close to the estimate of 28, the answer is reasonable. Carly Patterson’s total for the events other than the floor exercise was 28.45.

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 28.850 is close to the estimate of 29, the answer is reasonable. Carly Patterson’s total for the events other than the vault exercise was 28.85.

Using Mental Math to Add Decimals Adding Decimals Using Mental Math to Add Decimals Find the sum. A. 1.8 + 0.2 Think: 0.8 + 0.2 = 1. 1.8 + 0.2 = 2.0

Adding Decimals Check It Out Find the sum. A. 1.6 + 0.4 1.6 + 0.4 = 2.0 Think: 0.6 + 0.4 = 1.

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

Student Response Systems Adding Decimals Student Response Systems Identify the sum. 9.4 + 3.6 A. 12.8 B. 13 C. 14 D. 15.5

Student Response Systems Adding Decimals Student Response Systems Identify the sum. 19.91 + 9.09 A. 27 B. 28 C. 29 D. 30

Student Response Systems Adding Decimals Student Response Systems During a gymnastics competition, Jack scored the following points: 9.2, 7.8, and 6.5. What was Jack’s total score? A. 21.5 points B. 22.5 points C. 23.5 points D. 24.5 points