By dividing the gross profit by the gross income, you derive this gross profit margin. As an example, if your business grossed $20,000 in income with $15,000 in sales expenses, subtracting $15,000 from $20,000 gives you a gross profit of $5,000.Dividing $5,000 by $20,000 calculates a 0.25 gross profit margin.y dividing the gross profit by the gross income, you derive this gross profit margin. As an example, if your business grossed $20,000 in income with $15,000 in sales expenses, subtracting $15,000 from $20,000 gives you a gross profit of $5,000. Dividing $5,000 by $20,000 calculates a 0.25 gross profit margin.
Typical costs: 1  Stone countertops, including granite, other natural stone and quartz resin (engineered stone) cost $4-$150 per square foot, or $120-$4,500 for a typical 30 square foot kitchen countertop. 2  Laminate countertops cost $7-$30 per square foot, or $210-$900 for a typical kitchen.
Granite Tile: $5 - $15 per square foot Granite countertops come in two types of material: slab and tile. The type best suited for your project will depend on the square footage you need to cover, the number of seams you're willing to show and the amount of money you're willing to invest.