US Conversion Steps
(Dimensional Analysis)
1.
2.
3.
4.
5.
6.
7.
8.
Read the question to figure out what you have/know for information. The question will
provide you with information that identifies your starting point and your final destination.
•
Starting point = the number and unit provided by the question
•
Final destination = the units desired after converting
Using the information gathered from the question, write your starting point and your final
destination.
Determine the means in which you will get from your starting point to your final destination
(simply find “connections” or conversion factors between your starting and final unit).
Create a fraction by placing your starting point over one.
Multiply between fractions.
Write in the bottom unit of the new fraction. This should be the same as the top unit of
the previous fraction.
Write one set of “connections” or conversion factors into the fraction. Your bottom unit
will guide you.
Ask yourself, “Do I have the desired unit (final destination) on the top of the new
fraction?”
NO
(Go back to step 5)
9.
10.
YES
(Proceed to step 9)
Cancel any units that are diagonal. (This should leave you with only the units that represent
your final destination)
Multiply the top of the fractions…multiply the bottom of the fractions…divide the top by
the bottom.
Practice Conversions
1.
2.
3.
4.
5.
How many seconds are in 6 minutes?
360 seconds
How many centimeters are in 27 inches?
68.58 centimeters
If a truck weighs 15,356 pounds, how many tons is it?
7.678 tons
If you had 10.5 gallons of milk, how many pints would
you have?
84 pints
Students go to school for 180 days. How many minutes
is this equal to?
259,200 minutes
How many seconds are in 6 minutes?
Final Destination
6 minutes  seconds
Step 1 – Read the question and determine
what information it provides you with
(starting point & final destination)
1 minute = 60
Starting Point
Step 2 – Write down your
starting point and your final
seconds destination
Step 3 –
Determine how
you will get
from your
starting point to
your final
destination (list
any
Step 9 – Cancel all diagonal units.
“connections” or
Once this is done, your final
Step 5 – Multiply
Step
10 – Multiply the top of the
conversion
destination
should
be
only
8
–
Determine
if thisthe
topthe
between fractions Step 7 – Write Step
the
appropriate
fractions;
multiply
bottom
of
factors) Step 6 – Write in the bottom
unit
left – inunit
this(your
case seconds
unit
is
the
desired
Step 4 – Create
a fraction
conversion
into
thethe
fractions; divide the product
unit of
the new by
fraction
(this isfactor
final
destination).
In the
thisproduct
case of the
placing yourthe
starting
over
fraction.
bottom of
unitthe
willtop by
same point
as the
top
unit of Your
your the
answer is YES, so
we move
one previous fraction)
guide you.
bottom
on to step 9
(6 minutes) ( 60 seconds ) (6)(60 seconds)
=
1
( 1 minute )
(1)(1)
= 360 seconds
How many centimeters are in 27 inches?
Final Destination
27 inches  centimeters
Starting Point
Step 1 – Read the question and determine
what information it provides you with
(starting point & final destination)
Step 2 – Write down your
starting point and your final
centimeters destination
1 inch = 2.54
Step 3 –
Determine how
you will get
from your
starting point
to your final
destination (list
any
Step 9 – Cancel all diagonal units.
“connections”
Once this is done, your final
or conversion
Step 5 – Multiply
Step 10 – Multiply the top of the
should
be
only
factors)between fractions Step 7 – Write Step
8 fractions;
–destination
Determine
if thisthe
topthe
the
appropriate
multiply
bottom
of
Step 6 – Write in the bottom
unit
left unit
– in (your
this case
unit
is
the
desired
Step 4 – Create
a fraction
conversion
into
thethe
fractions; divide the product
unit of
the new by
fraction
(this isfactor
centimeters
final
destination).
In thisproduct
case of the
placing yourthe
starting
point
over
fraction.
Your
bottom
unit
will
of
the
top
same as the top unit of your the answer is YES,bysothe
we move
one previous fraction)
guide you.
bottom
on to step 9
(27 inches) ( 2.54 cm ) = (27)(2.54 cm)
(1)(1)
( 1 inch )
1
= 68.58 centimeters
If a truck weighs 15,356 pounds, how many
tons is it?
Final Destination
15,356 pounds  tons
Step 1 – Read the question and determine
what information it provides you with
(starting point & final destination)
Starting Point
Step 2 – Write down your
starting point and your final
ton
destination
2000 pounds = 1
Step 3 –
Determine how
you will get
from your
starting point to
your final
destination (list
any
Step 9 – Cancel all diagonal units.
“connections” or
Once this is done, your final
conversion
Step 5 – Multiply
Step 10 – Multiply the top of the
should
be
only
factors)between fractions Step 7 – Write Step
8 fractions;
–destination
Determine
if thisthe
topthe
the
appropriate
multiply
bottom
of
Step 6 – Write in the bottom
unitdesired
left – unit
in this
case tons
unit
is
the
(your
Step 4 – Create
a fraction
conversion
into
thethe
fractions; divide the product
unit of
the new by
fraction
(this isfactor
final
destination).
In the
thisproduct
case of the
placing yourthe
starting
over
fraction.
bottom of
unitthe
willtop by
same point
as the
top
unit of Your
your the
answer is YES, so
we move
one previous fraction)
guide you.
bottom
on to step 9
(15,356 lbs.) ( 1 ton )
(15,356)(1 ton)
=
1
( 2000 lbs. )
(1)(2000)
=
7.678 tons
If you had 10.5 gallons of milk, how many
pints would you have?
Final Destination
Starting Point
10.5 gallons  pints
Step 1 – Read the question and determine
what information it provides you with
(starting point & final destination)
1 gallon =
Step 2 – Write down your
4 quarts
starting point and your final
destination
1 quart = 2 pints
Step 3 –
Determine how
you will get
from your
starting point to
your final
destination (list
any
“connections” or
Step
5 – Multiply
Step
7Step
– Write
10
– the
Multiply
appropriate
the
toptop
of
conversion Step
Step56– –Multiply
WriteStep
in the
7 –bottom
Write
the
appropriate
Step
8Cancel
– Determine
if top
this
Step
Step
8
–
9
Determine
–
all
if
diagonal
this
units.
between
conversion
theisfractions;
factor
into
multiply
the (your
the
factors) between
unit of the
fractions
new fraction
conversion
(this6fractions
factor
is– Write
into
unit
the
the
desired
unit
Step
in
the
bottom
unit
Once
is
the
this
desired
is
done,
unit
your
(your
final
fraction.
bottom
Your
of bottom
the fractions;
unit
willdivide
the same
as the
fraction.
unit
bottom
final
unit
will
destination).
Inthe
this
case
Step 4 – Create
a fraction
bytop
unitofYour
ofyour
the
new
(this
isIn this
final fraction
destination
destination).
should
be
case
only
the
product
guide
you.
of
the
top
by
the
fraction)
guideasyou.
the
answer
is this
YES,
so
we
move
placing your starting previous
point over
the same
the answer
top
of–NO,
your
the
unitunit
left
is
in
so
we
case
move
pints
product to
of step
the bottom
one
previous fraction)
back toonstep
5 9
(10.5 gallons) (
1
(
4 quarts ) (
1 gallon ) (
(10.5)(4)(2 pints)
=
(1)(1)(1)
2 pints
1 quart
=
)
)
84 pints
Students go to school for 180 days. How many
minutes is this equal to?
Final Destination
Starting Point
180 days  minutes
Step 1 – Read the question and determine
what information it provides you with
(starting point & final destination)
1 day = 24
Step 2 – Write down your
hoursstarting
point and your final
destination
1 hour = 60 minutes
Step 3 –
Determine how
you will get
from your
starting point to
your final
destination (list
any
Step 9 – Cancel all diagonal units.
“connections” or
Step 5 – Multiply
Step 5 – Multiply Once this
Stepis10
– Multiply
the top
done,
your
final
conversion Step 6 – WriteStep
in
the
7
–
bottom
Write
the
appropriate
Step
7
–
Write
the
appropriate
Step
8the
– Determine
if
this top
between fractions between
ofbottom
fractions;
multiply
Step
6 fractions
–factor
Write
in the
destination
should
be the
only
unitthe
factors)
unit
of
the
new
fraction
conversion
(this
is
into
conversion
the
factor
into
the
Step 4 – Create a fraction by
Step
8 –the
Determine
if this
top
unit (this
is
desired
unit
(your
bottom
of the
fractions;
unit
of
the
new
fraction
is
left
–
in
this
case
minutes
the same
as the
fraction.
unit ofYour
yourbottom fraction.
unit
will
Your
bottom
unit
will
placing your starting
point
overtop
unit
is the
(your
final
destination).
Inunit
this
case
divide
thedesired
product
of
the
top
the
same
as
the
top
unit
of
your
previous
fraction)
guide
you.
guide
you.
one
final
destination).
case
the answer
is product
NO, In
so this
we
move
by the
of the
previous fraction)
the answer
YES,
backis to
stepso5we move
bottom
on to step 9
(180 days)
1
( 24 hours ) ( 60 minutes )
( 1 day ) ( 1 hour )
(180)(24)(60 minutes)
=
(1)(1)(1)
= 259,200 minutes
Online Tutorials
• http://www2.wwnorton.com/college/chemistry/gilber
t/tutorials/ch1.htm
(click on “view tutorial” for dimensional analysis)
• http://www.wfu.edu/~ylwong/chem/dimensionanalysis
/practice/index.html
(click on examples under dimensional analysis on the left side of the page)
• http://chemistry.alanearhart.org/Tutorials/DimAnal/
Interactive Quiz
• http://chem.lapeer.org/Exams/DimAnalQuiz.html