#### Answer

The tail length of an alligator whose body length is 6 feet is 5.4 feet.

#### Work Step by Step

We can write an equation that models an alligator’s tail length T, varying directly as its body length, B, as,
$T=kB$
Substitute B = 4 feet and T = 3.6 feet in the above equation.
$T=kB$
$3.6=k\times 4$
$0.9=k$
Substitute the value of $k$ into the equation, $T=kB$.
$T=0.9\times B$
Now, substitute 6 feet for B in $T=0.9\times B$ and solve for T, that is,
$\begin{align}
& T=0.9\times 6 \\
& =5.4
\end{align}$