120 to 180 is an equivalent ratio.
If you mean 3 12 then yes it is equivalent to 1 4
12 to 10
It is: 3 to 4
3:4
It is: 2 to 9
3:8
6 to 5
4 to 3
A ratio is equivalent to 12 to 10 when both numbers can be divided by the same factor to simplify the ratio. In this case, both 12 and 10 can be divided by 2 to get 6 and 5 respectively. Therefore, the equivalent ratio to 12 to 10 is 6 to 5. This means that for every 6 of one quantity, there are 5 of the other quantity.
No, it is not equivalent. Think of it this way. If you had £12 and I had £5 then you would have money in the ratio of 12 to 5 compared to me. If you then only had £5 and I had £17 (which represents the new ratio of 5 to 17) you would not agree that this was equivalent as a proportion (you would rightly feel that you had lost out)!
It is: 12/20 = 3/5