James's Sister is arranging rows of beads. She has 56 yellow beads and 120 blue beads. She wants to arrange them so that all the beads in a row are, are the same color, and so that each row has the same number of beads. What is the least number of rows James's sister can make?

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm