Chemistry 101 and Math Reactivation
The concept of equivalent fractions and the rule of multiplying fractions are required in order to perform unit conversions.
CONVERSIONS (as presented to students)
Multiplying Fractions :
1. Multiply.
a) 
b)
c)
(remove common factors prior to
multiplying)
Equivalent Fractions :
Consider the following set of fractions:
, 
, 
, 
, 
What do these fractions have in common? (They all
represent the same number, they all are equal to
. )
How can an equivalent fraction be obtained from a given fraction? (Multiply it by 1.)
=
=
Now, let’s convert 5 inches into feet.
1 foot = 12 inches, so 1 =
or 1 = 
5 inches ∙ = 
2. Now, you make the following conversions
a) 2.5 feet into inches. (30 inches)
b) 42 minutes into hours.
c) 40 miles into meters, given 1 mile = 1.609 km.
d) 1.2 gallons to mL, given 1 gallon = 3.8785 L.