3 lbs into 100 square feet.? Can you help me with these measurement's?

Since all 3 components are in per 100 sq ft, mix them together and you'll have 14 pounds of stuff, right? 14 pounds is the same as 224 oz. then divide this by 100 and come up with 2.24 ounces of the mixture per square ft. You need to make sure you mix it thoroughly and evenly.