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Copyright © Swun MathCopyright © Swun Math Grade 8 Unit 3 Lesson 4 P TE

Homework

Unit 3 · Lesson 4: Scientific Notation: Add & Subtract

Objective: I will add or subtract numbers in scientific notation.

Vocabulary Steps

Adding & Subtracting Scientific Notation

(4.342 × 10 ²) + (3.871 × 10 ³) =

Convert to same power:

(4.342 × 10 ²) + (38.71 × 10 ²)

Add decimals:

4.342 + 38.71 = 43.052

Bring down exponent:

43.052 × 10 ² =

Proper Scientific Form

4.3052 × 10 ³

1. Convert exponents to the same power of 10 (if
   needed).


2. Add or subtract the number (decimal).


3. Bring down the exponent on the ten.


4. Write in proper form.

Example # 1 Example # 2

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

(9.37 × 10-^7 ) – (1.421 × 10-^7 )

Solution:

• (9.37 – 1.421) × 10-7


• 7.949 × 10-7

Answer: 7.949 × 10-7

(5.312 × 10^1 ) + (6.421 × 10^2 )

Solution:

• 5.312 × 10^1 + 6.421 × 10^1 × 10^1

• 5.312 × 10^1 + 64.21 × 10^1

• (5.312 + 64.21) × 10^1

• 69.522 × 10^1  not written in scientific notation.

Answer: 6.9522 × 10^2

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