Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. Some rows and columns have fractions. The ratio of the connected pairs is 1/2, i. e. there are the following combinations of numbers in the two connected cells: 1 - 2, 2 - 4, 3 - 6 and 4 - 8 or vice versa.