Reading Strategies 1-4 Follow a Procedure

Name
LESSON
Date
Class
Reading Strategies
1-4 Follow a Procedure
When you have an exponent with a base of 10, the number is called
a power of 10.
You can use some simple rules to find products with powers of 10.
13 103
32.5 103
13 (10 10 10)
32.5 (10 10 10)
13 1,000
32.5 1,000
Move the decimal point
3 places to the right.
You need to add 3 zeros.
32,500.
Move the decimal point
3 places to the right.
You need to add 2 zeros.
You can use powers of 10 to write large numbers in scientific
notation. Scientific notation is used as a shortcut to write very large
or very small numbers.
To write 268,000,000 in scientific notation:
Step 1: Move the decimal point to create
a number between 1 and 10.
Step 2: The number of places the
decimal point is moved is the
value of the exponent.
2.6.8.0.0.0.0.0.0.
2.68 108
Move the decimal
point 8 places.
So, the exponent
is 8.
268,000,000 written in scientific notation is 2.68 108.
Use 2.8 105 to answer Exercises 1–4.
1. How many times is 10 a factor?
2. Rewrite the number with 10 as a repeated factor.
3. How many places will you move the decimal point?
How many zeros will be in the product?
4. What is the product of 2.8 x 105?
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All rights reserved.
33
Holt Mathematics
Problem Solving
1-4 Applying Exponents
Challenge
1-4 Computer Bytes
LESSON
LESSON
Write the correct answer.
Each byte in a computer’s memory represents about one character.
The major units of computer memory are kilobytes (KB), megabytes
(MB), and gigabytes (GB).
1 kilobyte
1,000 bytes
1 megabyte 1,000 kilobytes
1 gigabyte
1. Earth is about 150,000,000
kilometers from the sun. Write this
distance in scientific notation.
1 KB 1,000 bytes
1.5 108 km
1 MB 1,000 KB
1,000 megabytes
1 GB 1,000 MB
Write your answers using scientific notation.
1. In 1984, many personal computers
had 64 KB of active (RAM) memory.
How many bytes does this represent?
2. In 1992, many personal computers
had 40 MB of hard drive memory.
How many bytes does this represent?
4
6.4 10 bytes
$7,600,000,000,000;
9
11
1 10 bytes
2.5 10 bytes
Ming saved his computer files on floppy disks. Each disk holds up
to 1.44 MB of memory. He used these disks to transfer his files to
another computer.
5. How many bytes could each floppy
disk hold?
6. Ming’s new computer has 120 GB of
memory. How many disks could he
transfer if each disk held 1.2 MB?
1.44 106 bytes
100,000 disks
Rachel decided to back up her hard drive’s computer files by
copying them onto compact disks (CDs). Each CD can hold up
to 650 MB of memory, but Rachel saves only 600 MB on each.
7. How many bytes could each CD
potentially hold?
8. If Rachel backs up 6 GB of memory,
how many bytes of memory will she
need?
6.5 108 bytes
Choose the letter for the best answer.
5. China’s population in 2001 was
approximately 1,273,000,000.
Mexico’s population for the same
year was about 1.02 108. How
much greater was China’s population
than Mexico’s?
A 1,375,000,000
B 1,274,020,000
C 1,171,000,000
D 102,000,000
6. In mid-2001, the world population
was approximately 6.137 109. By
2050, the population is projected to
be 9.036 109. By how much will
world population increase?
F 151,730,000
G 289,900,000
H 1,517,300,000
J 2,899,000,000
7. The Alpha Centauri star system is
about 4.3 light-years from Earth. One
light-year, the distance light travels in
1 year, is about 6 trillion miles. About
how many miles away from Earth is
Alpha Centauri?
A 2.58 1013 miles
8. In the fall of 2001, students in
Columbia, South Carolina, raised
$440,000 to buy a new fire truck for
New York City. If the money had been
collected in pennies, how many
pennies would that have been?
F 4.4 106
G 4.4 105
H 4.4 107
B 6 1013 miles
C 1.03 1012 miles
D 2.58 109 miles
6 109 bytes
31
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Holt Mathematics
Canada
7.6 1012
4 10 bytes
4. By 2005, many personal computers
had 250 GB of hard drive memory.
How many bytes does this represent?
4,500,000,000 km
4. Canada is about 1.0 107 square
kilometers in size. Brazil is about
8,500,000 square kilometers in size.
Which country has a greater area?
3. At the end of 2004, the U.S. federal
debt was about $7 trillion, 600 billion.
Write the amount of the debt in
standard form and in scientific notation.
7
3. In 1997, many personal computers
had 1 GB of hard drive memory. How
many bytes does this represent?
2. The planet Neptune is about
4.5 109 kilometers from the sun.
Write this distance in standard form.
J 4.4 3 108
32
Copyright © by Holt, Rinehart and Winston.
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Holt Mathematics
Puzzles, Twisters & Teasers
1-4 Oh, the Power of Tens!
Reading Strategies
1-4 Follow a Procedure
LESSON
LESSON
Substitute the correct number for the letter or letters in each
equation. Use your answers to solve the riddle.
When you have an exponent with a base of 10, the number is called
a power of 10.
You can use some simple rules to find products with powers of 10.
13 103
32.5 103
13 (10 10 10)
32.5 (10 10 10)
13 1,000
32.5 1,000
4
P
5
2. 280,000 2.8 10
3. 592,000 I 105
5.92
4. 16,800 C 104
1.68
A
Move the decimal point
3 places to the right.
You need to add 3 zeros.
8
5. 5.4 10H 540,000,000
32,500.
1. 24,500 2.45 10E
6. 24,400,000 S 10
Move the decimal point
3 places to the right.
You need to add 2 zeros.
2.44; 7
What’s a Martian’s favorite snack?
You can use powers of 10 to write large numbers in scientific
notation. Scientific notation is used as a shortcut to write very large
or very small numbers.
S
P
A
C
E
C
H
I
P
S
2.44
5
7
1.68
4
1.68
8
5.92
5
2.44
To write 268,000,000 in scientific notation:
Step 1: Move the decimal point to create
a number between 1 and 10.
Step 2: The number of places the
decimal point is moved is the
value of the exponent.
Move the decimal
point 8 places.
2.6.8.0.0.0.0.0.0.
2.68 108
So, the exponent
is 8.
268,000,000 written in scientific notation is 2.68 108.
Use 2.8 105 to answer Exercises 1–4.
5 times
1. How many times is 10 a factor?
2. Rewrite the number with 10 as a repeated factor.
2.8 10 10 10 10 10
3. How many places will you move the decimal point?
How many zeros will be in the product?
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
5 places; 4
280,000
4. What is the product of 2.8 x 105?
33
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
106
34
Holt Mathematics
Holt Mathematics