Page 305 - Basic College Mathematics with Early Integers

282 C HAPTE R 4 I DECIMALS

PRACTICE 16 Example 16 Round -0.027 to the nearest hundredth.
Round -0.072 to the nearest
hundredth. Solution:
Step 1: Locate the digit to the right of the hundredths place.

hundredths place
–0.02 7
digit to the right
Step 2: Since the digit to the right is 5 or greater, we add 1 to the hundredths
digit and drop all digits to its right.
Thus, -0.027 is -0.03 rounded to the nearest hundredth.
Work Practice 16

The following number line illustrates the rounding of negative decimals.

0.03 0.027 0.025 0.02

In Section 4.3, we will introduce a formula for the distance around a circle. The
distance around a circle is given the special name circumference.
The symbol p is the Greek letter pi, pronounced “pie.” We use p to denote the
following constant:

circumference of a circle circumference
p =
diameter of a circle

diameter

The value p is an irrational number. This means if we try to write it as a decimal, it
neither ends nor repeats in a pattern.

PRACTICE 17 Example 17 p L 3.14159265. Round to the nearest hundredth.p
p L 3.14159265. Round top
the nearest ten-thousandth. Solution:
hundredths place 1 is less than 5.
3.14159265

Delete these digits.

Thus, 3.14159265 rounded to the nearest hundredth is 3.14. In other words,
Copyright 2012 Pearson Education, Inc.
p L 3.14 .
Work Practice 17

Answers
16. -0.07 17. p L 3.1416