Is 1 to 3, 2 to 9 equivalent or not. and is 2 : 3, 24 : 36 equivalent or not

1/3 is not equivalent to 2/9.

2/9 is already reduced to its lowest denominator (relative to its numerator).

As for your other question..

2/3 is equivalent to 24/36.

If we reduce 24/36 to its lowest denominator, it would be 2/3 (divide the top and bottom numbers by 12).

24 divided by 12 is 2.
36 divided by 12 is 3.

Therefore