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Number Theory/Percentages



I have seen in textbooks the following regarding how to change a
number to a percentage: "Multiply the number by 1, expressed as
100/100, to change the number to a fraction with the denominator
I have seen this explanation in at least two textbooks.

Why is the number "1" used in this method? I know that any
fraction, in which the numerator and denominator are the same,
equals 1, but what is the logical reason for multiplying by 1? I also know that when a number is multiplied by 1, it does not change its value. It would be more reasonable to multiply by just 100/100 and not mention anything regarding the number "1", but I suppose there is some logical reason.

I thank you for your reply.

Hi Kenneth
I think that most students would realise that multiplying by the number 1 does not change the value of the fraction, but might not realise that multiplying by 100/100 did the same, unless they were reminded that 1 could be expressed as 100/100.

Best wishes for your researches.


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