Find the unknown number in the proportion. Round answer to the nearest thousandths when necessary.
1/2=x/9
To find the unknown number x in the proportion \( \frac{1}{2} = \frac{x}{9} \), we can solve for x using cross-multiplication.
We'll multiply both sides of the proportion by the product of the denominators to eliminate the fractions. This means multiplying both sides by 2 * 9 = 18.
So, \( \frac{1}{2} \cdot 18 = \frac{x}{9} \cdot 18 \)
This simplifies to:
\( 9 = 2x \)
Now, divide both sides by 2 to solve for x:
\( x = \frac{9}{2} \)
\( x = 4.5 \)
Therefore, the unknown number x is 4.5, which to the nearest thousandths is 4.500.