Basic Mathematics for College Students

Chapter 2 Summary and Review 199

Dividing two integers

To divide two integers, divide their absolute values.

1.The quotient of two integers that have the same

(like) signs is positive.

2.The quotient of two integers that have different

(unlike) signs is negative.

To check divisionof integers, multiply the quotient

and the divisor.You should get the dividend.

DEFINITIONS AND CONCEPTS EXAMPLES

Divide:

Find the absolute values: and.

Divide the absolute values, 21 by 7, to get 3.

The final answer is positive.

Check: The result checks.

Divide:

Find the absolute values: and.

Divide the absolute values, 54 by 9, to get 6.

Then make the final answer negative.

Check: 6(9) 54 The result checks.

 54

9  6

0  540  54 090  9

 54

9

3(7) 21

 21

 7

 3

0  210  21 0  70  7

 21

 7

Division with 0

If 0 is divided byany nonzero integer, the quotient

is 0.

Division ofany nonzero integer by 0 is undefined.

Divide, if possible:

is undefined.  6

0 is undefined.

 2

0

0

(20) 0

0

 8

 0

Problems that involve forming equal-sized groups

can be solved by division.

USED CAR SALES The price of a used car was reduced each day

by an equal amount because it was not selling. After 7 days, and a

$1,050 reduction in price, the car was finally purchased. By how

much was the price of the car reduced each day?

Divide the change in the price of the car by the

number of days the price was reduced.

The negative result indicates that the price of the car was reducedby

$150 each day.

1,050

7

 150

79. Fill in the blanks: We know that because
    .


80. Check using multiplication to determine whether
    .
    Divide, if possible.


81. 
    
    
    
    82. 
        
    
    
    
    


82. 
    
    
    
    84. 
        
    
    
    
    


83. 
    
    
    
    86. 
        
    
    
    
    


84. 
    
    
    
    88. 
        
    
    
    
    


85. 
    
    
    
    90. 
        
    
    
    
    


86. 
    
    
    
    92. 
        
    
    
    
    

 4

0

0

 5

 272

16

1,058

 46

150,000 3,000 24,000 (60)

 673

 673

 10

 1

 64

(8) 72
(9)

 14

7

25

 5

 152

(8) 18

()

 15

5

 3 93. Divide by 3.

94. Find the quotient of and.


95. PRODUCTION TIME Because of improved
    production procedures, the time needed to produce
    an electronic component dropped by 12 minutes
    over the past six months. If the drop in production
    time was uniform, how much did it change each
    month over this period of time?


96. OCEAN EXPLORATION The Puerto Rico
    Trench is the deepest part of the Atlantic Ocean. It
    has a maximum depth of 28,374 feet. If a remote-
    controlled unmanned submarine is sent to the
    bottom of the trench in a series of 6 equal dives,
    how far will the vessel descend on each dive?
    (Source: marianatrench.com)

 125  25

 96

REVIEW EXERCISES

SECTION 2.5 Dividing Integers