Basic Mathematics for College Students

Use a metric ruler to measure lengths.

Parts of a metric ruler, scaled in centimeters, and a ruler scaled in inches are shown
below. Several lengths on the metric ruler are highlighted.

1 2 3

12345678910

2.54 cm = 1 in.

53 mm

1 cm

(Actual size)

Metric system

American system

Inches

Centimeters

2

5.4 Metric Units of Measurement 457

EXAMPLE (^1) Find the length of the nail shown below.
StrategyWe will place a metric ruler below the nail, with the left end of the ruler
(which could be thought of as 0) directly underneath the head of the nail.
WHYThen we can find the length of the nail by identifying where its pointed end
lines up on the tick marks printed in black on the ruler.
Solution
The longest tick marks on the ruler (those labeled with numbers) mark lengths in
centimeters. Since the pointed end of the nail lines up on 6, the nail is 6 centimeters
long.
1234567
Centimeters
Self Check 1
To the nearest centimeter, find
the width of the circle.
Now TryProblem 23
Self Check 2
Find the length of the jumbo
paper clip.
Now TryProblem 25
EXAMPLE (^2) Find the length of the paper clip shown below.
StrategyWe will place a metric ruler below the paper clip, with the left end of the
ruler (which could be thought of as 0) directly underneath one end of the paper
clip.
WHYThen we can find the length of the paper clip by identifying where its other
end lines up on the tick marks printed in black on the ruler.
Copyright 2010 Cengage Learning, Inc. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.