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Homework

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

Objective: I will to add and 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

Add or subtract the number (decimal).

Bring down the exponent on the ten.

*Another option is to convert to standard form and subtract.

Example # 1 Example # 2 Directions: Simplify. Write solution in scientific notation.

(2.75 × 10^3 ) + (9.1 × 10^3 )

Solution:

Since the powers of ten are the same, use the
distributive property to combine the lead numbers
and add them.

2.75 × 10^3 + 9.1 × 10^3

(2.75 + 9.1) × 10^3 Add first (parentheses).

11.85 × 10^3  Not in Scientific Notation

11.85 needs to change to 1.185 for Scientific
Notation

Answer: 1.185 × 10^4
or

Convert to standard form:

2750 + 9100 = 11,850

Convert solution 11,850 into Scientific Notation
form.
Answer: 1.185 × 104

(6.6 × 10–^5 ) – (3.5 × 10–^5 )

Solution:

Since the powers of ten are the same, use the
distributive property to combine the lead numbers
and add them.

6.6 × 10-5 – 3.5 × 10-5

(6.6 – 3.5) × 10-5 Subtract first (parentheses).

3.1 × 10-5

Answer: 3.1 × 10-5
or

Convert to standard form:

0.000066 – 0.000035= 0.000031

Convert solution 0.000031 into Scientific Notation
form.
Answer: 3.1 × 10 –5

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Date: ___

Homework