Acme shoe store marked $6 off of the price of each pair of shoes in stock. If the store
has 220 pairs of shoen in stock, what is the
total reduction in price?

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.