Question

2 to 4 and 12 to 20 are these equivalent

Answer 1

They are not equivalent, you can cross multiply

Answer 2

No, i would look at these side by side.
A ratio is like a fraction so
2/4 and 12/20
Let's try simplifying 12/20.
Divide each side by 4 and that is 3/5.
This definitely does not equal 2/4
- now let's try this from the 2/4 perspective:
2/4
LCD would be 20. Multiply top and bottom by 5. It would equal 10/20 and not 12/20.
So either way it is not equivalent