A grain of sand weighs about 1x10^-6 gram.reaserchers at the university of Hawaii estimate there are 7.5 x 10^18 grains of sand on earth. How much do all of those grains of sand weigh.
[7.5 X 10^18] X [1.0 X 10^-6] =7,500,000,000,000 grams/ 10^6=7,500,000 Metric Tons.
