1.2 Adding Whole Numbers 21
Success Tip Estimates can be greater than or less than the exact answer. It
depends on how often rounding up and rounding down occurs in the
estimation.
4 Solve application problems by adding whole numbers.
Since application problems are almost always written in words, the ability to
understand what you read is very important.
The Language of Mathematics Here are some key words and phrases that
are often used to indicate addition:
gain increase up forward rise more than
total combined in all in the future altogether extra
EXAMPLE 7
Sharks The graph on
the right shows the number
of shark attacks worldwide
for the years 2000 through
- Find the total number
of shark attacks for those
years.
Strategy We will carefully
read the problem looking
for a key word or phrase.
WHY Key words and
phrases indicate which
arithmetic operation(s)
should be used to solve the
problem.
Solution
In the second sentence of the problem, the key word total indicates that we should
add the number of shark attacks for the years 2000 through 2007. We can use
vertical form to find the sum.
The total number of shark attacks worldwide for the years 2000 through 2007
was 526.
Add the digits, one column at a time, working from
right to left. To simplify the calculations, we can
look for groups of two or three numbers in each
column whose sum is 10.
5
7
3
9
68
62
57
65
61
63
71
526
Self Check 7
AIRLINE ACCIDENTSThe numbers
of accidents involving U.S. airlines
for the years 2000 through 2007
are listed in the table below. Find
the total number of accidents for
those years.
2000
Year
2001 2002 2003 20042005 2006 2007
79
68
61 63
71
62 65
90
80
70
60
50
40
30
20
Number of shark attacks—worldwide 10
57
Year Accidents
2000 56
2001 46
2002 41
2003 54
2004 30
2005 40
2006 33
2007 26
The Language of Mathematics To solve the application problems, we must often
translate the words of the problem to numbers and symbols. To translate means to
change from one form to another, as in translating from Spanish to English.
Now TryProblem 97
Source: University of Florida