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Proportions A proportion is a statement that to ratios or rates are equal. It can be given as a sentence in words, but most often a proportion is an algebraic equation The arithmetic equation 3 5 3 X 35 = 105 21 35 is a proportion because its cross products are equal. and 5 x 21 = 105 Proportions are solved by using this cross-product rule Example #2 Example #1: 4 = 9 Y 36 72 1.5 12 y

Proportions A proportion is a statement that to ratios or rates are equal. It can-example-1
User Jeremy Evans
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2 Answers

18 votes
18 votes

in Example #2,
\( y = 0.25 \) or
\( (1)/(4) \) when rounded to the nearest hundredth.

in Example #1,
\( y = 16 \).

Here are the detailed steps to solve the proportions for
\( y \):

Example #1:

The proportion is given by:


\[ (4)/(9) = (y)/(36) \]

To solve for
\( y \), cross-multiply to get:


\[ 4 * 36 = 9 * y \]


\[ 144 = 9y \]

Now, divide both sides by 9 to isolate
\( y \):


\[ y = (144)/(9) \]


\[ y = 16 \]

So, in Example #1,
\( y = 16 \).

**Example #2:**

The proportion is given by:


\[ (72)/(1.5) = (12)/(y) \]

To solve for
\( y \), cross-multiply to get:


\[ 72 * y = 12 * 1.5 \]


\[ 72y = 18 \]

Now, divide both sides by 72 to isolate
\( y \):


\[ y = (18)/(72) \]


\[ y = 0.25 \]

So, in Example #2,
\( y = 0.25 \) or
\( (1)/(4) \) when rounded to the nearest hundredth.

User Bondsmith
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14 votes
14 votes

We have the following:

example #1


\begin{gathered} (4)/(9)=(y)/(36) \\ 9\cdot y=4\cdot36 \\ y=(4\cdot36)/(9) \\ y=16 \end{gathered}

example #2


\begin{gathered} (72)/(1.5)=(12)/(y) \\ 72\cdot y=12\cdot1.5 \\ y=(12\cdot1.5)/(72) \\ y=0.25 \end{gathered}

User Partial
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