Lesson 4-8 Pages 186-190
Scientific
Notation
Lesson Check 4-7
What you will learn!
1. How to express numbers in
standard form and in scientific
notation.
2. How to compare and order
numbers written in scientific
notation.
Scientific notation
What you really need to know!
When you deal with very large
numbers like 5,000,000 or very
small numbers like 0.0005, it is
difficult to keep track of place
value. Numbers such as these
can be written in scientific
notation.
What you really need to know!
A number is expressed in
scientific notation when it is
written as a product of a
factor and a power of 10. The
factor must be greater than
or equal to 1 and less than
10.
What you really need to know!
It looks like a
multiplication problem.
The decimal point is
going for a walk!
Example 1:
Express each number in
standard form:
4
10
4 395 x
43,950.
What you really need to know!
Since our number system is
based on 10, scientific
notation always uses 10
raised to a power.
Place Value Chart
2
10
1
10
0
10
Hundreds
Tens
Ones
.
-1
10
-2
10
-3
10
Tenths
Hundredths
Thousandths
Example 2:
Express each number in
standard form:
-6
10
6 79 x
0.00000679
Example 3:
Express each number
in scientific notation:
800,000
5
8.0 x 10
Example 4:
Express each number
in scientific notation:
1,320,000
6
1.32 x 10
Example 5:
Express each number
in scientific notation:
0 0119
-2
1.19 x 10
Example 6:
Use the table:
Estimate how
many times
farther Pluto is
form the Sun
than Mercury is
from the Sun.
(5.90 x
9
10 )
÷ (5.80 x
7
10 )
Pluto is about
100 times
farther from
the Sun than
Mercury!
Example 7:
The diameters of Mercury, Saturn, and
Pluto are 4.9 x 103 km, 1.2 x 105 km,
and 2.3 x 103 km respectively. List the
planets in order of increasing diameter.
Pluto, Mercury, Saturn
Page 188
Guided Practice
#’s 3-11
Read:
Pages 186-188
with someone at
home and study
examples!
Homework: Pages 189-190
#’s 12-48 even
#’s 51-59
Lesson Check Ch-4
Page
733
Lesson 4-8
Lesson Check Ch-4
Study Guide and Review
Pages
191-194
#’s 1-65
(Odd answers in back of book)
Prepare for Test!
Page
195
#’s 1-30
1.A number is divisible by 2 if it is even.
(The
ones digit is 2, 4, 6, 8, 0)
A number is divisible by 3 if the sum of the digits
equal a multiple of 3.
A number is divisible by 5 if the ones digit is 0 or
5.
A number is divisible by 6 if it is divisible by both 2
and 3.
A number is divisible by 10 if the ones digit is 0.
2.A prime number has exactly two factors.
Examples: 2, 3, 5, 7, 11, 13, 17, 19, …
A composite number has three or more factors.
Examples: 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, …
0 and 1 are neither prime or composite!
3.A fraction is in simplest form when the only
common factor between the numerator and
denominator is 1.
Examples:
a
b
7x
8y
4. Yes
5. No
4
6. 3
7. (-2)3a4
8. 2  2  3  r  r
9. 2  5  5  x  y  y
10. 7(1 + 3p)
11. 14
12. 18
13. 4ab
14. 3/5
15. 2/3
16. 7m2/4
9
17. 5
10
18. -24x
19. w4
2
20. 1/4
21. 1/t6
3
1/(yz)
22.
23. 0.09
24. 0.005206
25. 37,100
5
26. 3.45 x 10
6
27. 1.68 x 10
28. 7.2 x 10-4
29. 3/4
30. A
Prepare for Test!
Pages
196-197
#’s 1-21