Three pounds of fertilizer covers 900 feet. How many pound of fertilizer will cover 2,100 feet?

To solve this problem, you can make a proportion:

3/900 = x/2100

In this case, the x represents the pounds that will be needed to cover 2,100 feet.

The first step is to cross multiply like this:

3 * 2100 = 900 * x

Now you can simply the equation.

6300 = 900x

Now you divide both sides by 900 to cancel it out.

7 = x

So, your answer is 7 pounds.