A trucking company delivered 4,604 cubic yards of gravel. They also delivered 3 times that many cubic yards
of sand. How many cubic yards of sand did they deliver?

answer: 4  

the square root of 16 is 4. it is a very simple mathematic concept. a square root when a number multiplied by itself will result in a number. here, the number 16 comes when 4 is multiplied by 4. hence the square root of 16 is 4. you can always figure out a square root by the inverse operation of squaring.