Transcript Course 2 Lesson 5

Lesson 5-8
Pages 227-231
Comparing and
Ordering Rational
Numbers
Lesson Check 5-7
What you will learn!
How to compare and
order fractions, decimals,
and percents.
Common denominator
Least common denominator (LCD)
Rational numbers
What you really need to know!
To compare fractions, rewrite
them so they have the same
denominator. The least
common denominator
(LCD) of two fractions is the
LCM of their denominators.
What you really need to know!
Another way to
compare fractions is to
express them as
decimals. Then
compare the decimals.
What you really need to know!
Rational
Numbers
5.2
0.8
Integers
-6
Whole
Numbers
8
-10
13
1
2
2
5
3
1
-1.444…
Find the LCD:
5
7
and
6
9
5 3 15
 
6 3 18
7 2 14
 
9 2 18
Find the LCD:
3
1
and
4
7
3 7 21
 
4 7 28
1 4 4
 
7 4 28
Example 1:
Joe and his younger brother
both had a math test last
Friday. Joe scored 48 points
out of 60 and his brother
scored 55 points out of 75.
Who got the better score?
Example 1:
48
 48  60  0.8  80%
60
55
 55  75  0.73  73%
75
Joe had the better score.
Example 2:
According to the Pet Food
Manufacturer’s Association,
11 out of 25 people own
large dogs and 13 out of 50
own medium dogs. Do more
people own large or medium
dogs?
Example 2:
11 11  2 22


 44%
25 25  2 50
13 13  1 13


 26%
50 50  1 50
Large!
Example 3:
7
Order , 0.6, and 72%
10
from least to greatest.
7
 7  10  0.70
10
0.6  0.60
72%  72  100  0.72
7
0.6, , 72%
10
Example 4:
Find the number that is rational.
A
B
C
D
0.12345…
0.123123…

0.10203…
5
0
-7
4.5
3/4
3/4
5
0
5
Natural
Numbers
Whole
Numbers
-7
0
5
Integers
4.5
-7
0
5
Rational
Numbers
Page 229
Guided Practice
#’s 3-12
Read:
Pages 227-229
with someone at
home and study
examples!
Homework: Page 230-231
#’s 14-50 even
#’s 54, 55, 58-64
Lesson Check Ch 5
Page
576
Lesson 5-8
Lesson Check Ch 5
Study Guide and Review
Pages
232-234
#’s 1-68
(Odd answers in back of book)
Prepare for Test!
Page
235
Lesson Check Ch 5 V2
Practice Test Answers
#’s 1-20
Lesson Check Ch 5
Practice Test Answers
Prepare for Test!
Pages
236-237
#’s 1-17