Audio Transcript Auto-generated
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for this video we are going to review ratios
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first. What are ratios?
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The ratio is used when comparing one number or term to another number.
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And when you're writing a ratio, that could be written one of three ways
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with a colon
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with the word T O
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two
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or
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as a fraction.
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And the examples given are already the same way
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2-3.
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When the ratio is represented by a fraction.
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The result is that ratios are similar to fractions.
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They each have two terms
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and can be simplified
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by reducing
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A ratio comparing 10 dimes to 5/4
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is
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Shown
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as a fraction. 10/5.
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When the ratio is given as a fraction,
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it's very important to look at the order which the terms are listed in the problem.
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The term listed first will be written in the numerator is position.
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The term listed second will be written as the denominator.
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It's very important to follow the order and not write the
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ratio
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upside down.
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That would be an incorrect ratio and not function properly.
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Once the
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pressure was written
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it can be reduced.
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We look at the greatest common factor or the largest
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number that will divide into both of those terms.
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With the example of 10/5,
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we know that the number five
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is a factor for both of those numbers.
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Five goes into 51 time
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and five goes into
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10 2 times
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giving us the simplified
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Ratio of 2 : one.
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But just because fractions and ratios look the same. There are a couple of rules
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for fractions that you cannot do with. The ratio
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ratios cannot be written as a mixed number of fractions
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and a ratio can never be simplified down to a whole number
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are simplified ratio was 2/1, 2 to 1,
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and it cannot be written simply as to once you do that you have no more terms,
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You're no longer comparing two terms, You're only representing one.
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This is because
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a fraction is representing the same labeled units such as slices of cake
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and a ratio maybe labeling different terms such as quarters and dimes.
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And we'll do an example of a fraction that
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a local animal shelter rescues cats and dogs.
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And currently they have eight cats
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and four dogs
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to represent this as a ratio. We would count the number of cats, it's listed first
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And there are eight cats.
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And we're comparing that to dogs
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And there are four dogs.
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So my ratio would be 8-4 and represented in either of the three ways.
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If we represent it as a fraction are
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enumerators position would be eight and our denominators position before
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we look at simplifying those.
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Our greatest common factor that would go into this would be 44 goes into 41 time
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And four goes into 82.
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And that would represent a simplified
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what allows us to organize
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the cats and dogs into groups of two cats for every one
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dog.
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We can represent that simplified ratio
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As 2-1 in three different ways