1/2+1/31/2 + 1/31/2+1/3^2 = 3/6+2/63/6 + 2/63/6+2/6^2 = 5/65/65/6^2 = 25/36
1/21/21/2^2 + 1/31/31/3^2 = 1/4 + 1/9 = 9/36 + 4/36 = 13/36
1/21/21/2 + 2 1/2 1/3 + 1/31/31/3^2 = 1/2 + 1/3 + 1/6 + 1/9 = 3/6 + 2/6 + 1/6 + 2/18 = 6/6 = 1
1/2+1/31/2 + 1/31/2+1/3^2 = 3/6+2/63/6 + 2/63/6+2/6^2 = 5/65/65/6^2 = 25/36
1/21/21/2^2 + 1/31/31/3^2 = 1/4 + 1/9 = 9/36 + 4/36 = 13/36
1/21/21/2 + 2 1/2 1/3 + 1/31/31/3^2 = 1/2 + 1/3 + 1/6 + 1/9 = 3/6 + 2/6 + 1/6 + 2/18 = 6/6 = 1