1. Multiplying Decimals

2. Objectives Objective: We will find the product of two decimals. Language Objective: We will use key words whole number, product, and decimal.

3. WordDefinitionExample whole number a counting number from one to infinity 7 95 489 decimal a number written as a whole number and a part of a whole number 4.2 four and two tenths 5.73 five and seventy-three hundredths product the answer to a multiplication problem 9 x 6 = 54 Vocabulary

4. Steps for Multiplying Decimals 1.Line up the decimals as if they were whole numbers. (You DON’T have to line up the decimal point!) 2.Multiply as if the numbers were whole numbers. 3.Go back to the decimal and count the total number of decimal places to the right of the decimal points. 4.Move the decimal point that many places to the left of the product.

5. Multiplying Decimals 9.52 x 3.8 36.176

6. Multiplying Decimals 13.2 x 5.45 71.94

7. Multiplying Decimals 1.24 x 8 9.92

8. Multiplying Decimals 0.003 x 6.4 0.0192

9. Multiplying Decimals 7.49 x 1.02 7.6398

10. Multiplying Decimals 1.93 x 3.7 7.141

11. Multiplying Decimals 4.351 x 7.25 31.5375

12. Multiplying Decimals 2.45 x 2.81 6.8845

13. Multiplying Decimals 6.892 x 41.34 284.91528

14. Word Problems Marty runs tract at Mountain View High School in Tucson. He ran the 200-meter dash in 35.2 seconds. It took Jenny 1.2 times as long as Marty to run the 200-meter dash. How long did it take Jenny to run the 200-meter dash? 42.24 seconds

15. Word Problems Zach bought 5.5 pounds of oranges for $0.90 per pound. How much did Zach spend on oranges? $4.95

16. Word Problems Kara weighs 74.6 pounds. Her mom weighs 1.8 times as much as she does. How much does Kara’s mom weigh? 134.28 pounds

17. Word Problems Mary is buying candy for her birthday party. She bought 3.2 pounds of gummy bears for $1.25 per pound. She bought 5.75 pounds of M&Ms for $4.50 per pound. She bout 2.8 pounds of licorice for $2.99 per pound. How much money did Mary spend in all? $38.25

18. Conclusion What is the most important thing to remember when multiplying a whole number and a decimal? How is this different from adding decimals?