Why do we use division when we use per something?

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Cash Fulton
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Why do we use division/fractions to represent per something?
 
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phinds said:
Three per hundred, for example, means 3 out of 100, so we can write it as a ratio, 3:100, or a fraction, 3/100
Doesn't really answer my question. I am asking why that is.
 
Cash Fulton said:
Doesn't really answer my question. I am asking why that is.
Why it is, is because of what the words mean. When we say, for example, 6 per cent (literally 6 per 100) we are expressing a ratio: ##\frac 6 {100}##. It's similar for units such as mph (miles per hour). We are talking about a ratio of miles driven per (divided by) the time in hours.
 

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