Page 72 - Math Course 1 (Book 1)

LCM (Least Common Multiple)

REAL WORLD EXAMPLE

Order Rational Numbers

FOOTBALL

1
2
Dane’s football team usually practices for hours.
2
The table below shows how many hours from normal they practiced
each day this week. Order the practices from shortest to longest.

Mon Tues Wed Thurs

3 3 5 2
- 1 - 1
8 4 6 3

Step 1: Order the negative fraction f rst. The LCD of Step 2: Order the positive fraction. The LCD of
6 and 8 is 24. 3 and 4 is 12.

5 20 3 9 2 8 3 9
- = - - = - 1 = 1 1 = 1
6 24 8 24 3 12 4 12
Compare the negative fractions. Compare the negative fractions.
8
Since - 20 < - 9 , then - 5 < - 3 Since < 1 9 , then 1 2 < 1 3
1
24 24 6 8 12 12 3 4
5 3 2 3
Since - < - <1 < 1 the order of the practices from shortest to longest is
Answer 6 8 3 4
Wednesday, Monday, Thursday, and Tuesday.

Your Turn!
Weather
Compare Fractions

Replace • with <, >, or = to make 5 9 a true The table shows the rainfall of four months
statement. 21 14 compared to the overall yearly average of 3 1
5
A. < inches of rainfall for Columbus, Ohio. Order the
B. > months from least rainfall to most rainfall.
C. = A. Jul, Apr, Jan, Oct
D. none of the above Average Rainfall
B. Jan, Oct, Jul, Apr Month (inches)
C. Oct, Jan, Apr, Jul 7
D. Jan, Oct, Apr, Jul Jan - 8
Apr -1 3
16
Answer 7
Jul -1 32

11
Oct -
16

Answer

64