To check,
add
bottom
to topChapter 1 Summary and Review 115Amazon (South America) 4,049 mi
Mississippi-Missouri (North America) 3,709 mi
Nile (Africa) 4,160 mi
Ob-Irtysh (Russia) 3,459 mi
Yangtze (China) 3,964 mib. Construct a line graph of the data.51015Permits issuedYear2001 2002 2003 20042005 2006 20072008Line graph- GEOGRAPHY The names and lengths of the five
longest rivers in the world are listed below. Write
them in order, beginning with the longest.
SECTION 1.2 Adding Whole Numbers
To add whole numbers,think of combining
sets of similar objects.
Vertical form: Stack the addends. Add the
digits in the ones column, the tens column, the
hundreds column, and so on. Carry when
necessary.DEFINITIONS AND CONCEPTS EXAMPLES
Add:
CarryingAddend
Addend
Addend
Sum10
1
,82
91
2
5,467
499
16,85810,8925,467 499
(Source: geography.about.com)Commutative property of addition:The order
in which whole numbers are added does not
change their sum.
Associative property of addition:The way in
which whole numbers are grouped does not
change their sum.By the commutative property, the sum is the same.By the associative property, the sum is the same.(175) 25 17 (525)
6 5 5 6
To solve the application problems, we must
often translatethe key wordsand phrasesof
the problem to numbers and symbols. Some
key words and phrases that are often used to
indicate addition are:
gain increase up forward
rise more than total combined
in all in the future extra altogetherTranslate the words to numbers and symbols:
VACATIONS There were 4,279,439 visitors to Grand Canyon
National Park in 2006. The following year, attendance increased by
134,229. How many people visited the park in 2007?
The phrase increased byindicates addition:4,279,439 134,229
The number of
visitors to the
park in 2007
To estimate a sum, use front-end roundingto
approximate the addends. Then add.Estimate the sum:The estimate is 10,600.Round to the nearest thousand.
Round to the nearest hundred.
Round to the nearest thousand.