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Copyright © Swun MathCopyright © Swun Math Grade 8 Unit 3 Lesson 6 P TE

Homework

Unit 3 · Lesson 6: Scientific Notation:
Multiply & Divide

Objective: I will multiply or divide numbers in scientific notation.

Vocabulary Steps

Multiplying in Scientific Notation

1. Multiply coefficients.


2. Add exponents.
   (3 × 102 ) ( 5 × 104 ) =

3 × 5 = 15

10 2+4 = 10^6

15 × 106

1.5 × 107

Proper Scientific Form

Dividing in Scientific Notation^

1. Divide coefficients.


2. Subtract exponents.

(15 × 106 ) ÷ ( 3 × 102 ) =

15 ÷3 = 5

10 6-2 = 10^4

5 × 104

1. Check for numbers in scientific notation.


2. If multiplying-
   
   
   • Multiply coefficients.
   
   
   • Add exponents.
   
   
   
   


3. If dividing-
   
   
   • Divide coefficients.
   
   
   • Subtract exponents.
   
   
   
   


4. Write in scientific notation.

Example # 1 Example # 2

Directions: Simplify the expression. Write solution in scientific notation.

(1.2 × 10^2 ) × (0.8 × 10^3 )

Solution:

• Verify that each number is written in scientific notation.


• (1.2 × 10^2 ) × (0.8 × 10^3 ) not in scientific notation.


• (1.2 × 10^2 ) × (8 × 10^2 )


• (1.2 × 8) × (10^2 × 10^2 )


• 9.6 × 102 + 2


• 9.6 × 10^4
  Answer: 9.6 × 10^4

(2.5 × 10^2 ) ÷ (5 × 10^3 )

Solution:

• Verify that each number is written in scientific notation.


• 2 .5⋅ 10

2

5⋅ 10^3

• 25.^5 ⋅^10

2

103

• 0.5⋅^101023


• 0.5⋅ 10 2−3


• 0.5 × 10–1 not in scientific notation


• 5 × 10–2
  Answer: 5 × 10–2

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