two eights make one quarter so it takes threes times as many to make three quarters. So, 6 eights make three quarters. ( A eighth of a dollar is called a bit so 2 bits is a quarter and 6 bits is 75 cents. There is an old song that ends with "Shave and a haircut - six bits.)
there are 2 quarters in 4 eighths
12 quarters will make $3
4 quarters go into one dollar. So 12 quarters = 3 dollars.
Three of them.