A) To find out how much moisture is in the sand in terms of the dry sand, we need to take the difference in weight, and find out what the percentage is compared to the dry sand, like this:
32 (wet sand) - 30.8 (dry sand) = 1.2 (moisture)
(moisture)/(dry sand)=(percentage of moisture compared to dry sand)
1.2/30.8 = .0389, or 3.89% of the weight is moisture, compared to the dry sand.
B) We know that there are 1728 cubic inches in a cubic foot (12 in x 12 in x 12 in). Our sample is 36 cubic inches. We then set up the ratio "One (cubic foot) is to 1728 cubic inches, as what is to 36 cubic inches?" to find out how many cubic feet are in our sample.
Our problem looks like this: 1/1728 = x/36.
When we do the math, we find out that our sample is .02083333 cubic feet.
Now we need to set up an equation to find out how much the wet sand weighs per cubic foot. We know that wet sand is 32 ounces per .0208333 cubic feet. Our equation looks like 32/.020833 = x/1. When we do the math, we find out that wet sand will weigh about 1536.2457 ounces per cubic foot, or about 96.0153 pounds (1536.2457/16 ounces in a pound)
Hope that helped!