612095206-Math-week-4-ppt-Addition-and-Subtraction-of-Decimal-Numbers.pptx

CDGEYFCHD

1. After going through this lesson, you are expected to add and subtract decimals and mixed decimals through ten thousandths without or with regrouping. Lesson Objectives and Tips on Decimals Tip on Rounding off Numbers Add 1 to the digit in the rounding place if the digit to its right is 5 or greater otherwise leave the digit unchanged. Drop all digits after the rounding place.

2. REVIEW ON ROUNDING OFF DECIMALS

3. Math Tricks on Rounding off Decimals

4. Math Tricks on Rounding off Decimals Let’s do this Learning Task 1. Estimate the sum of the given situation by rounding the amount to highest peso value. Write your answer in your notebook.

5. ADD AND SUBTRACT DECIMALS AND MIXED DECIMALS THROUGH TEN THOUSANDTHS

6. TIPS ON ADDING AND SUBTRACTING DECIMALS Adding and Subtracting decimals is similar to the process of adding and subtracting whole numbers. Decimals through ten thousandths have four digits after the decimal points. Here are the steps on how to add and subtract decimal numbers through ten thousandths.

7. STEPS ON HOW TO ADD AND SUBTRACT DECIMALS

8. Arrange the digits in columns and align the decimal points. STEPS ON ADDING AND SUBTRACTING DECIMALS Insert zeros in empty decimal place values (if needed) so that all of the numbers have the same number of decimals places. Add or subtract as with whole numbers.

9. LET’S TRY THIS Add 0.25 + 0.03 + 0.0756 Arrange the digits in columns and align the decimal points. Insert zeros in empty decimal place values (if needed) so that all of the numbers have the same number of decimals places. Add or subtract as with whole numbers.

10. LET’S DO THIS 0.008 + 0.02 + 0.0087 + 0.39 + 0.3661 2. 0.0053 + 0.71 + 0.09 + 0.015 + 0.173 3. 0.007 + 0.3531 - 0.126 + 0.15 - 0.08 4. 0.0785 + 0.0662 Solution Solution Solution Solution

11. LET’S DO THIS Learning Task 3: Solve the problems below. Write your answer in your notebook. Three pails have different capacities. The small pail can hold 0.0062 liters of water. The bigger pail has a capacity of 0.3792 liters while the biggest pail holds 0.9914 liters. Find the total amount of water that can be stored in the pails. 2. A gasoline tank of a car has 4.2893 liters of gasoline. It is driven to a gasoline station and filled with 9.6782 liters. If the tank has 12.4894 after driving to the school and office. How many liters of gasoline were used? 3. Three sticks measuring 0.3265 meters, 0.2160 meters and 0. 4213 meters were put end to end. What was their total length?

12. EXAMPLES Learning Task 4: Solve the problem. Estimate the total amount. Mr. Cruz’s monthly income is ₱ 75, 000.00. He divide his income to the following expenses: Food: ₱ 22, 450.89 Recreation: ₱5, 676. 63 Clothes: ₱ 15,670.25 Transportation: ₱ 10,067.15 Other amount goes to savings. How much is the savings? Learning Task 5: Solve the given problems. Write your answer in your notebook.

13. PROBLEM SOLVING INVOLVING ADDITION AND SUBTRACTION OF DECIMALS NUMBERS

14. In solving problems, you need to understand first the given problem and plan for which operation (s) to use. You may draw an illustration to help you visualize your plan. Then solve and check. Tips on Solving Problems Involving Addition and Subtraction of Decimals

15. Understand POLYA’S 4 – STEPS PROCESS Plan Solve Check

16. POLYA’S 4 –STEPS PROCESS

17. LET’S TRY THIS Refer to the table below of liquid and its weight. Answer the question that follows. 1. How heavy is 4 gallons of kerosene ? 2. How much more does a gallon of seawater weigh than a gallon of drinking water? 3. Which is heavier, 1 gallon of oil or 2 gallons of gasoline? How much heavier? 1. How heavy is 4 gallons of kerosene ? 2. How much more does a gallon of seawater weigh than a gallon of drinking water? 3. Which is heavier, 1 gallon of oil or 2 gallons of gasoline? How much heavier? 6.664 + 6.664 + 6.664 + 6.664 = 26.656 1 gallon of Kerosene = 6.664 1 gallon of seawater = 8.58 1 gallon of drinking water = 8.33 8.58 – 8.33 = 0.25 1 gallon of oil = 7.497 2 gallons of gasoline = 11.328 Answer: 2 gallons of gasoline by 3.831

18. Understand POLYA’S 4 – STEPS PROCESS Plan Solve Check

19. LET’S DO THIS In a sale, a microwave costs ₱ 2,999.99. Its price has been reduced by ₱ 500.00. What was its price before the sale? Understand What is asked in the problem ? The price of a microwave before the sale What is/are the given facts? Cost of microwave = ₱ 2,999.99 ₱ 500.00 less Plan What is the mathematical sentence What is the operation used? Addition ₱ 2,999.99 + ₱ 500.00 = n Solve ₱ 2999.99 + ₱ 500.00 ₱ 3499.99 Check ₱ 3499.99 __ ₱ 500.00 ₱ 2999.99

20. LET’S TRY THIS Learning Task 2 Solving word problems involving addition and / or subtraction of decimal and mixed decimal numbers with or without regrouping. 1. Mr. Lagrazon has a 15 - hectare Banana plantation and a 12.8567 hectare sugarcane plantation. How much bigger is the Banana plantation than the sugarcane plantation? 2. Mang Juan has 5 hectares of land. He sold 2.0725 hectares to his neighbor. How many hectares of land does he own now?

21. GROUP ACTIVITY BREAKOUT ROOMS https://docs.google.com/forms/d/e/1FAIpQLSdYtWQBlagkh8yJRrcu-bT_cx7u2r6SsZDO6TcjohnXUrrslg/viewform?usp=sf_link

22. LET’S TRY THIS Learning Task 3 Learning Task 4