Multiplying_Decimal_Numbers_Presentation.pptx

multiplying decimals with real life examples

1. Multiplying Decimal Numbers Understanding decimals through real-world examples

2. Lesson Objectives After this lesson, you will be able to: - Multiply decimal numbers accurately. - Understand how decimal multiplication applies in real life. - Solve word problems involving decimal multiplication.

3. Steps in Multiplying Decimals 1. Ignore the decimal points and multiply the numbers as whole numbers. 2. Count the total number of decimal places in both factors. 3. Place the decimal point in the product according to the total decimal places. 4. Check your answer for reasonableness.

4. Example: 3.2 × 1.4 Step 1: Ignore the decimals → Multiply 32 × 14 = 448 Step 2: Count decimal places → 1 (in 3.2) + 1 (in 1.4) = 2 Step 3: Place decimal → 4.48 ✅ Final Answer: 3.2 × 1.4 = 4.48

5. Real-World Example 1: Shopping Maria buys 2.5 kilograms of apples. Each kilogram costs $3.25. To find the total cost: → Multiply 2.5 × 3.25 = 8.125 → Total cost = $8.13 (rounded to the nearest cent)

6. Real-World Example 2: Gasoline A car needs 7.5 gallons of gas. Each gallon costs $4.29. → Multiply 7.5 × 4.29 = 32.175 → Total cost = $32.18

7. Real-World Example 3: Measurement A rectangular garden is 2.4 meters wide and 3.6 meters long. To find the area: → Multiply 2.4 × 3.6 = 8.64 → The garden area is 8.64 square meters.

8. Practice Problems Try these on your own: 1. 4.5 × 2.3 = ? 2. 6.25 × 0.4 = ? 3. A candy bar costs $1.75. You buy 3.5 of them. How much do you spend?

9. Summary - Multiply as if whole numbers. - Count and place the decimal point. - Apply multiplication of decimals in everyday life like shopping, travel, and measurements.