Question

using appropriate properties of rational number solve it​

Answer 1

The use of prepositions in such phrases is more based on conventional usage than on logic or on grammar per se. (So for example “close up the store” and “close down the store” mean pretty much the same thing).

So I can tell you that in contemporary American English, “the answer to this question” is proper and common usage. And that “the answer of this question” is perfectly understandable (and could be logical), but sounds awkward and unusual. I suspect that British English etc would be the same but defer to others on that.

Answer 2

Answer:

Refers to the attachment