Solving a rate problem

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Solving a rate problem
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Solving a rate problemIf gas is 66 cents
per L, what is this in dollars per gallon?
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If gas is 66 cents per L, what is this in dollars
per gallon?In this problem we have two units
cents and gallons
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If gas is 66 cents per L, what is this in dollars
per gallon?We have to be able to turn the
words 66 cents per liter into a term we can use
in a calculation.
66centsper liter
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Now we can begin our calculationWe first write
what we are givenWe will be changing both
given units, cents and liters, in this problem
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We will now change one unit at a time to the
desired unit.
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We will now change one unit at a time to the
desired unit.Remember, we always multiply
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We will now change one unit at a time to the
desired unit. It does not matter which one we
start with so we will start with liters.
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We will now change one unit at a time to the
desired unit. We start by writing liters on
the top of the next term.
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We will now change one unit at a time to the
desired unit.
We start by writing liters on the top of the
next term.
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We will now change one unit at a time to the
desired unit.
On the bottom we will place the units we want
to replace for liters, qt.
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Now we put quarts on the bottom
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We put 1.08 in front of qt since 1l 1.08 qt.
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We have now converted liters into quarts.
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Now we will convert quarts into gallons
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We put qt on the top of the 3rd term
Now we will convert quarts into gallons
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Then we put gal on the bottom
Now we will convert quarts into gallons
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Now we are ready to put numbers in front of the
units
Now we will convert quarts into gallons
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Now we are ready to put numbers in front of the
units
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Now we are ready to put numbers in front of the
units
Since we know that 1 gal 4 qt. , those are the
numbers we place in front of those units
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We are half way done. We have converted one of
the units, liters, into gallons.
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We are half way done. We have converted one of
the Units, liters, into gallons.
Now we will change cents into dollars
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On the bottom of the 4th term we put the units
cents
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On the bottom of the 4th term we put the units
cents
Cents on the bottom of the 4th term will factor
out with cents on the top of the first term.
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Dollars are the unit that we want to factor in.
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Dollars are the unit that we want to factor in.

So dollars go on top of the 4th term.
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Now we need to put numbers in front of the
units of the 4th term.

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Now we need to put numbers in front of the
units of the 4th term.

We know that 1 dollar 100 cents. So those are
the appropriate numbers.
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When we factor the units we are left with
dollars/gallon
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When we factor the units we are left with
dollars/gallon
Those are the units we want.
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When we factor the units we are left with
dollars/gallon
Those are the units we want.
Now we can do the math
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When we do the math,
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When we do the math,
everything on the bottom gets divided,
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When we do the math,
everything on the bottom gets divided,
and everything on top gets multiplied
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When we do the math,
into our calculator, we put 66 / 1.08 x 4 / 100
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Our fewest number of significant digits is 2 from
66cents, so we have only 2 digits in our
answer 2.4
into our calculator, we put 66 / 1.08 x 4 / 100
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Another way of showing our answer would be
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Another way of showing our answer would be
This would be the same as saying 2.4 dollars per
gallon.
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If gas is 66 cents per L, what is this in dollars
per gallon?