1.1 An Introduction to the Whole Numbers 3EXAMPLE (^1) Airports Hartsfield-Jackson Atlanta International Airport
is the busiest airport in the United States, handling 89,379,287 passengers in 2007.
(Source: Airports Council International–North America)
a.What is the place value of the digit 3?
b.Which digit tells the number of millions?
StrategyWe will begin in the ones column of 89,379,28 7. Then, moving to the left,
we will name each column (ones, tens, hundreds, and so on) until we reach the digit 3.
WHY It’s easier to remember the names of the columns if you begin with the
smallest place value and move to the columns that have larger place values.
Solution
a.89, 3 79,287 Say, “Ones, tens, hundreds, thousands, ten thousands, hundred
thousands” as you move from column to column.
3 hundred thousands is the place value of the digit 3.
b. 89 ,379,287
The digit 9 is in the millions column.
Self Check 1
CELL PHONESIn 2007, there were
255,395,600 cellular telephone
subscribers in the United States.
(Source: International
Telecommunication Union)
a.What is the place value of the
digit 2?
b.Which digit tells the number
of hundred thousands?
Now TryProblem 23
2 Write whole numbers in words and in standard form.
Since we use whole numbers so often in our daily lives, it is important to be able to
read and write them.
Reading and Writing Whole Numbers
To write a whole number in words, start from the left. Write the number in
each period followed by the name of the period (except for the ones period,
which is not used). Use commas to separate the periods.
To read a whole number out loud, follow the same procedure. The commas
are read as slight pauses.
The Language of Mathematics The word andshould not be said when
reading a whole number. It should only be used when reading a mixed number
such as 5 12 (five and one-half) or a decimal such as 3.9 (three and nine-tenths).
The Language of Mathematics Each of the worked examples in this
textbook includes a Strategy andWhyexplanation. A stategyis a plan of action
to follow to solve the given problem.
EXAMPLE (^2) Write each number in words:
a. 63 b. 499 c.89,015 d.6,070,534
Strategy For the larger numbers in parts c and d, we will name the periods from
right to left to find the greatestperiod.
WHY To write a whole number in words, we must give the name of each period
(except for the ones period). Finding the largest period helps to start the process.
Solution
a.63 is written:sixty-three. Use a hyphen to write whole numbers from 21 to 99 in
words (except for 30, 40, 50, 60, 70, 80, and 90).
b.499 is written:four hundred ninety-nine.
Self Check 2
Write each number in words:
a. 42
b. 798
c.97,053
d.23,000,017
Now TryProblems 31, 33, and 35