1. Course 3, Lesson 1-6
Write each expression using a positive exponent.
1. 7–6 2. (–10)–3 3. x–5
Simplify. Express using positive exponents.
4. 6–2 • 65 5.
6. –5x2y–2 • 3x–3y5n 7.
8. Order 11–3, 111, 113, 110, and 11–1 from least to greatest.
3
5
8
8
3 2
2
a b
a b
2. Course 3, Lesson 1-6
ANSWERS
1.
2.
3.
4. 63
5. 82
6.
7.
8. 11–3, 11–1, 110, 111, 113
6
1
7
3
1
10
5
1
x
3
15y
x
b
a
3. WHY is it helpful to write numbers in
different ways?
The Number System
Course 3, Lesson 1-6
8. Course 3, Lesson 1-6
The Number System
Words Scientific notation is when a number is written as the
product of a factor and an integer power of 10. When the
number is positive the factor must be greater than or equal
to 1 and less than 10.
Symbols , where 1 ≤ a < 10 and n is an integer
Example 425,000,000 =
×10na
84.25×10
13. 1
Need Another Example?
2
Step-by-Step Example
3. Write the number in scientific notation.
3,725,000
3,725,000 = 3.725 × 1,000,000 The decimal point moves 6 places.
= 3.725 × 106 Since 3,725,000 > 1, the exponent is positive.
15. 1
Need Another Example?
2
Step-by-Step Example
4. Write the number in scientific notation.
0.000316
0.000316 = 3.16 × 0.0001 The decimal point moves 4 places.
= 3.16 × 10–4 Since 0 < 0.000316 < 1, the exponent is negative.
17. 1
Need Another Example?
2
Step-by-Step Example
5. Refer to the table at the right.
Order the countries according
to the amount of money
visitors spent in the United
States from greatest to least.
1.06 × 107
Canada and
United Kingdom
↓
1.06 > 1.03
Group the numbers
by their power of 10.
Mexico
and India
↓
1.03 × 107
7.15 × 106
1.83 × 106
>
7.15 > 1.83
Compare the decimals.↑
United
Kingdom
↑
Canada
↑
Mexico
↑
India
18. Answer
Need Another Example?
The following table lists the maximum
frequency for the colors of the visible light
spectrum. List the colors from greatest to
least frequency.
violet, blue, green, orange, red
19. 1
Need Another Example?
Step-by-Step Example
6. If you could walk at a rate of 2 meters per
second, it would take you 1.92 × 108 seconds to walk to
the moon. Is it more appropriate to report this time as
1.92 × 108 seconds or 6.09 years? Explain your reasoning.
The measure 6.09 years is more appropriate. The number
1.92 × 108 seconds is very large so choosing a larger unit
of measure is more meaningful.
20. Answer
Need Another Example?
One light year is about 9.46 × 1012 kilometers
or 9.46 × 1018 millimeters. Is it more appropriate
to report this length as 9.46 × 1012 kilometers or
9.46 × 1018 millimeters? Explain your reasoning.
9.46 × 1012 kilometers; the number is very large
so choosing a larger unit of measure is more
meaningful.
21. How did what you learned
today help you answer the
WHY is it helpful to write numbers in
different ways?
Course 3, Lesson 1-6
The Number System
22. How did what you learned
today help you answer the
WHY is it helpful to write numbers in
different ways?
Course 3, Lesson 1-6
The Number System
Sample answers:
• Scientists often use very large or very small numbers
which can be written in scientific notation.
• Scientific notation is a more concise way of writing
these numbers.
23. Explain the steps
used to write a number
between 0 and 1 in
scientific notation. Use
an example to illustrate
your explanation.
Ratios and Proportional RelationshipsThe Number System
Course 3, Lesson 1-6