Unit 1 Chapter 1 Section 7 Multiplying Rational Numbers.notebook
September 28, 2015
Bellringer:
Adding and subtracting mixed numbers requires several steps. You must find the least common denominator, write equivalent fractions, add or subtract, and simplify. Since it is possible to make a mistake in any of these steps, accuracy is very important.
Which of the four problems below are correct? Correct the ones that are wrong.
32
7 3
1731
9 25
4 5
7
+ 2 38
____
10
3
+ 54
____
­ ____
12
1
­____
4
5 37
12 1
13 11
8 3
56
20
12
1
20
Jul 26­12:38 PM
1
Unit 1 Chapter 1 Section 7 Multiplying Rational Numbers.notebook
September 28, 2015
Unit 1
Chapter 1 Section 7
Multiplying Rational Numbers
Objective: To multiply rational numbers
The rules for multiplying integers can be extended to all rational numbers. .
.Negative =
Positive Positive Positive =
.
.Positive =
Negative Negative Negative =
Jun 6­8:17 PM
2
Unit 1 Chapter 1 Section 7 Multiplying Rational Numbers.notebook
September 28, 2015
Examples:
Multiplying Same Sign Rational Numbers
• When both numbers are positive, the product is _____________.
• When both numbers are negative, the product is _____________.
• Change mixed fractions into improper fractions and multiply across.
• Use your calculator.
_
_
1) Find the product.
.
3
1
a) (4 )(2 )
4
2
b) 4.75 2.2 2
15
c) (­8 )(­ )
5
24
d) ­8.6 ­3.4
.
Multiplying Different Sign Rational Numbers
• When both numbers have different signs, the product is _____________.
• Change mixed fractions into improper fractions and multiply across.
• Use your calculator.
2) Find the product.
3
1
a) (5 )(­2 )
5
4
b) ­4.75 2.2 2
1
c) (4 )(­1 )
7
5
d) ­8.6 3.4
Jun 10­10:28 AM
3
Unit 1 Chapter 1 Section 7 Multiplying Rational Numbers.notebook
September 28, 2015
Application:
3) Freediving is an underwater activity in which the diver does not 1
use scuba gear. When James freedives, he can descend 1 ft per 3
second below sea level. How far below sea level can James descend in 5 seconds?
4) Mary is conducting a science experiment. She changes the 3
temperature of a chemical solution by ­ F each minute. What is the 4
total change in the temperature of the chemical solution after 11 minutes?
5) The Dancemania dancing studio sent 2/3 of its dancers to a competition. If there are 36 dancers, how many dancers did the studio send to the competition?
Jun 16­10:50 AM
4
Unit 1 Chapter 1 Section 7 Multiplying Rational Numbers.notebook
September 28, 2015
Classwork (Partners)
Textbook Pages 40 & 41, #'s 8 - 36 even
Jun 10­11:05 AM
5