Answer
You'd need to place $558ft^{3}$ in an evaporation basin to collect 125 lb of sea salt.
Work Step by Step
We assign the variable:
x = amount (cubic feet) of sea water
Step 1:
Using unit conversion with the data given in the problem,
$\frac{64lb}{ft^{3}}*xft^{3}=64xlb$
This is the total amount of salt in the water.
Step 2:
To find the amount of sea water, we must multiply the pounds of salt to the parts of dissolved salt by water so this has to equal the total pounds of sea salt.
$64x*0.0035=125$
Solving for $x$, we get
$x=\frac{125}{64*0.0035}$
$x=558.04ft^{3}\approx558ft^{3}$
Step 3:
You'd need to place $558ft^{3}$ in an evaporation basin to colect 125 lb of sea salt.
