What ratios form a proportion. Use equivalent ratios to test each pair

Question

1. 4/9 , 2/3
2. 6/15 , 9/12
3. 12/16 , 15/20
4. 18/20 , 24/30

Answer 1

well, to make a proportion, the two ratios must be equal
4/9 = 4/9
2/3 = 6/9
so, what do you think?
check the others.

Answer 2

Thanks so much for helping me.