Find x in the following proportions.
`x:3::57:19`

Answer

To solve the proportion \( x:3::57:19 \), we can follow these steps:

### Step 1: Write the proportion as a fraction
The proportion \( x:3::57:19 \) can be written as:
\[ \frac{x}{3} = \frac{57}{19} \]

### Step 2: Cross-multiply
To eliminate the fractions, we can cross-multiply:
\[ x \cdot 19 = 3 \cdot 57 \]

### Step 3: Calculate the right side
Now, calculate \( 3 \cdot 57 \):
\[ 3 \cdot 57 = 171 \]

### Step 4: Set up the equation
Now we have:
\[ 19x = 171 \]

### Step 5: Solve for \( x \)
To find \( x \), divide both sides by 19:
\[ x = \frac{171}{19} \]

### Step 6: Calculate the value of \( x \)
Now, perform the division:
\[ x = 9 \]

### Final Answer
Thus, the value of \( x \) is:
\[ \boxed{9} \]

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