Basic Mathematics for College Students

118 Chapter 1 Whole Numbers

Subtract.

33. 
    
    
    
    34. 
        
    
    
    
    


34. Subtract 10,218 from 10,435.


35. 
    


36. 
    
    
    
    38. 
        
    
    
    
    


37. Check the subtraction using addition.


38. Fill in the blank: because.


39. Estimate the difference:181,23244,810

20  8  12

8,017

6,949

1,168

7,800

5,725

750  259  14

5,2315,177

343

 269

148  87

43. BANKING A savings account contains $12,975.
    If the owner makes a withdrawal of $3,800 and
    later deposits $4,270, what is the new account
    balance?


44. SUNNY DAYS In the United States, the city of
    Yuma, Arizona, typically has the most sunny
    days per year—about 242. The city of Buffalo, New
    York, typically has 188 days less than that.
    How many sunny days per year does Buffalo
    have?

REVIEW EXERCISES

Country Land area (square miles)

Russia 6,592,115

Canada 3,551,023

(Source:The World Almanac, 2009)

SECTION 1.4 Multiplying Whole Numbers

Multiplication of whole numbersis repeated

addition but with different notation.

DEFINITIONS AND CONCEPTS EXAMPLES

Repeated addition:

The sum of four 6’s Multiplication

6  6  6  6  4  6  24

Multiply:

Since 1,000 has three zeros, attach three

0’s after 8.

Since 10,000 has four zeros, attach four

0’s after 43.

160 and 20,000 have a total of five trailing

zeros. Attach five 0’s after 32.

160 20,0003,200,000

43(10,000)430,000

8 1,0008,000

To find the product of a whole number and

and so on,attach the number of

zeros in that number to the right of the whole

number.

This rule can be extended to multiply any two

whole numbers that end in zeros.

10, 100, 1,000,

To write multiplication, we use a times symbol

,a raised dot , and parentheses ( ). 4  6 4  6 4(6)or(4)(6)or (4)6

Vertical form:Stack the factors. If the bottom

factor has more than one digit, multiply in

steps to find the partial products. Then add

them to find the product.

Multiply:

Factor

Factor

Partial product: 4 163

Partial product: 20 163

Product

163

 24

652

3260

3,912

24  163











Multiply 16 and 2

to get 32.



42. LAND AREA Use the data in the table to
    determine how much larger the land area of Russia
    is compared to that of Canada.