I had a pretty basic question about dimensional analysis. According to this site :
"Dimensional Analysis (also called Factor-Label Method or the Unit Factor Method) is a problem-solving method that uses the fact that any number or expression can be multiplied by one without changing its value. It is a useful technique. The only danger is that you may end up thinking that chemistry is simply a math problem - which it definitely is not."
There are a couple of things I don't understand about dimensional analysis. Firstly, how does "the fact that any number or expression can be multiplied by one without changing its value" actually tie in to the full concept of dimensional analysis?
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In the actual setup of the problem you're solving. Why are you using multiplication?
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What if you had something like 730 days is 2 years and so on? Are you taking the product of the numerators and dividing that by the product of the denominators or what? I don't actually get what's going on in this problem.
I'm aware I may be complicating certain aspects of this problem, but I have problems with understanding simple concepts when I don't really understand the root of the concept.
Apologies for the inexperience, please try to explain this as simply as possible. Thanks.