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2 Computation with Real Numbers
This chapter presents the rules for computing with real numbers—often called
signed numbers. Before proceeding with addition, subtraction, multiplication,
and division of signed numbers, the discussion begins with comparing num-
bers and fi nding the absolute value of a number.
Comparing Numbers and Absolute Value
Comparing numbers uses the inequality symbols shown in Table 2.1.
Graphing the numbers on a number line is helpful when you com-
pare two numbers. The number that is farther to the right is the greater
number. If the numbers coincide, they are equal; otherwise, they are
unequal.
Table 2.1 Inequality Symbols
INEQUALITY SYMBOL EXAMPLE READ AS
< 2 < 7 “2 is less than 7”
> 7 > 2 “7 is greater than 2”
≤ 9 ≤ 9 “9 is less than or equal to 9”
≥ 5 ≥ 4 “5 is greater than or equal to 4”
≠ 2 ≠ 7 “2 is not equal to 7”
