 # 5. 63 3.73.7 x 1 2 4 4 39 098 1 16+ 13 1 8 1 0 1 2 two one three.

## Presentation on theme: "5. 63 3.73.7 x 1 2 4 4 39 098 1 16+ 13 1 8 1 0 1 2 two one three."— Presentation transcript:

5. 63 3.73.7 x 1 2 4 4 39 098 1 16+ 13 1 8 1 0 1 2 two one three.

 You do not line up the factors by the decimal.  Instead, place the number with more digits on top.  Line up the other number underneath, at the right.  Multiply  Count the number of decimal places (from the right) in each factor.  Use the total number of decimal places in your two factors to place the decimal in your product.

2.618 has more digits (4) than 0.53 (3), so it goes on top. 2. 618 0. 53x 4 2 58 1 7 00 4 90 3 13 000000+ 457 1 831 Decimal Places three two five.

EXAMPLE 1 Multiplying Decimals 5.82 0.41 2 decimal places 5 8 25 8 2 2 3 2 8 4 decimal places ––– + ––––––  2.3 8 6 2 ––––––– 1234

6.45 18 2 decimal places 0 decimal places 5160 645 –––––– 116.10 EXAMPLE 2 Multiplying Decimals ––– + ––––––  After you place the decimal point, you can drop any zeros at the end of an answer. 2 decimal places Multiplying Decimals ANSWER 6.45  18 = 116.1

Write a zero before the 7 as a placeholder so that the number has 5 decimal places. 6.45 18 2 decimal places 0 decimal places 5160 645 –––––– 116.10 1.273 0.06 3 decimal places 2 decimal places 76380.0 5 decimal places EXAMPLE 3 Multiplying Decimals ––– + ––––––  –––––––  ––– + After you place the decimal point, you can drop any zeros at the end of an answer. 2 decimal places Multiplying Decimals

15.3 6.5x 5 1 6 2 7 08 1 1 3 9+ 54 1 99 one two.

Commutative Property of Multiplication: Factors can be multiplied in any order. Example: 12 x 5 = 5 x 12 Associative Property of Multiplication: Factors can be grouped in any way. Example: (2 x 3) x 5 = 2 x (3 x 5)

If a Decimal number is multiplied by 10,100, 1000 etc., the decimal shifts to the right side according to the number of Zeroes. Ex) Multiply 12. 277 x 10 = 122. 77 Ex) Multiply 132. 277 x 100 = 13227. 7 Ex) Multiply 42. 587 x 10000 = 425870. 0

Download ppt "5. 63 3.73.7 x 1 2 4 4 39 098 1 16+ 13 1 8 1 0 1 2 two one three."

Similar presentations