Using each of the digits 0-6 only once, make two equivalent ratios (proportions). There should be 6 solutions.

The answers are in bold in my Step-by-step explanation.

Step-by-step explanation:

0:0, 0:1, 0:2, 0:3, 0:4, 0:5, 0:6

1:0, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6

2:0, 2:1, 2:2, 2:3, 2:4, 2:5, 2:6

3:0, 3:1, 3:2, 3:3, 3:4, 3:5, 3:6

4:0, 4:1, 4:2, 4:3, 4:4, 4:5, 4:6

5:0, 5:1, 5:2, 5:3, 5:4, 5:5, 5:6

6:0, 6:1, 6:2, 6:3, 6:4, 6:5, 6:6

1:1 = a whole, so the others are similar.