Transcript Conversion Factors and Unit Cancellation

Chapter 1.3
Conversion Factors
and
Unit Cancellation
I- Unit Conversion
a) 1 foot = 12 inches
b)
1 foot
12 inches
= 1
These are “Conversion factors”
Which one you use depends on
what you want to do
c) 12 inches
1 foot
= 1
Steps to converting units
1) Write the number (with units) that you want to
convert.
2) Multiply it by a conversion factor, written as a
fraction
3) Make sure the OLD units cancel (tells you which
way the conversion factor goes)
4) Multiply the numbers on top and divide by the
numbers on the bottom.
How many inches in 4.3 feet?
1) Write the number (with
units) that you want to
convert.
4.3ft
12𝑖𝑛
2) Multiply it by a conversion 4.3ft ×
1𝑓𝑡
factor, written as a fraction
12𝑖𝑛
1𝑓𝑡
3) Make sure the OLD units
cancel (tells you which way the
conversion factor goes)
4.3ft ×
4) Multiply the numbers on top
and divide by the numbers on
the bottom.
4.3 x 12in = 51.6in
Convert 52.8 hours to days
1) Write the number (with
units) that you want to
convert.
52.8 hrs
1𝑑𝑎𝑦
2) Multiply it by a conversion 52.8hrs ×
24ℎ𝑟𝑠
factor, written as a fraction
1𝑑𝑎𝑦
24ℎ𝑟𝑠
3) Make sure the OLD units
cancel (tells you which way the
conversion factor goes)
52.8hrs ×
4) Multiply the numbers on top
and divide by the numbers on
the bottom.
52.8
= 2.2 days
24
How many kilometers are in
2.5 miles?
1) Write the number
(with units) that you
want to convert.
2) Multiply it by a
conversion factor,
written as a fraction
2.5 miles
2.5 miles X
1.609𝑘𝑚
1 𝑚𝑖𝑙𝑒
3) Make sure the OLD units
cancel (tells you which way the
conversion factor goes)
2.5 miles X
4) Multiply the numbers on top
and divide by the numbers on
the bottom.
2.5 x 1.609= 4.02 km
1.609𝑘𝑚
1 𝑚𝑖𝑙𝑒