CH. 2 - MEASUREMENT
III. Unit Conversions
I
II
III
(p. 40 - 42)
A. SI Prefix Conversions
1. Find the difference between the
exponents of the two prefixes.
2. Move the decimal that many places.
To the left
or right?
A. SI Prefix Conversions
532 m
NUMBER
UNIT
0.532 km
= _______
=
NUMBER
UNIT
A. SI Prefix Conversions
move right
move left
Prefix
mega-
Symbol
M
Factor
106
kilo-
k
103
BASE UNIT
---
100
deci-
d
10-1
centi-
c
10-2
milli-
m
10-3
micro-

10-6
nano-
n
10-9
pico-
p
10-12
A. SI Prefix Conversions
1) 20 cm =
0.2
______________
m
32
2) 0.032 L = ______________
mL
3) 45 m =
45,000
______________
nm
0.0805
4) 805 dm = ______________
km
Unit Conversions
 The “Factor-Label” Method
 Units, or “labels” are canceled, or
“factored” out
g
cm 

g
3
cm
3
Factor Label Method
 Steps:
1. Identify starting & ending units.
2. Line up conversion factors so units
cancel.
3. Multiply all top numbers & divide by
each bottom number.
4. Check units & answer.
Factor Label Method
 Lining up conversion factors:
1 in = 2.54 cm
=1
2.54 cm 2.54 cm
1 in = 2.54 cm
1=
1 in
1 in
Factor Label Method
 How many milliliters are in 1.00 quart of
milk?
qt
1.00 qt
mL

1L
1.057 qt
1000 mL

1L
= 946 mL
Factor Label Method
 You have 1.5 pounds of gold. Find its
volume in cm3 if the density of gold is
19.3 g/cm3.
cm3
lb
1.5 lb

1 kg 1000 g 1 cm3

2.2 lb
1 kg
19.3 g
= 35 cm3
Factor Label Method
5) Your European hairdresser wants to cut
your hair 8.0 cm shorter. How many
inches will he be cutting off?
cm
in
8.0 cm  1 in
2.54 cm
= 3.2 in
Factor Label Method
6) GHS football needs 550 cm for a 1st
down. How many yards is this?
cm
550 cm
yd

1 in

1 ft 1 yd

2.54 cm 12 in 3 ft
= 6.0 yd
Factor Label Method
7) A piece of wire is 1.3 m long. How many
1.5-cm pieces can be cut from this wire?
cm
pieces
1.3 m  100 cm
1m

1 piece
1.5 cm
= 86 pieces