#### Answer

$x=35$ feet

#### Work Step by Step

The problem can be solved using the following proportion:
$\frac{3.5ft}{60in}=\frac{x}{50ft}$
first, convert all measurements to feet, by dividing inches by 12.
$\frac{3.5ft}{5ft}=\frac{x}{50ft}$
Cross multiply
$5*x=3.5*50$
multiply
$5x=175$
divide both sides by 5
$x=35$ feet