Answer
The extremes are $x$ and $24$. The means are $8$ and $18$.
$x = 6$
Work Step by Step
A proportion takes the following form:
$\frac{a}{b} = \frac{c}{d}$, where $a$ and $d$ are the extremes and $b$ and $c$ are the means.
In this exercise, $a = x$, $b = 8$, $c = 18$, and $d = 24$.
The extremes are $x$ and $24$. The means are $8$ and $18$.
Let's solve for $x$:
$\frac{x}{8} = \frac{18}{24}$
Use the cross products property to get rid of the fractions:
$24x = 144$
Divide each side by $24$ to solve for $x$:
$x = 6$