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#1 Re: Help Me ! » Is a decimal a percentage "in the US"? » 2015-11-18 07:45:27

Hi and thanks for the prompt replies! I saw this kind of conversions in my son's textbook. However, still I cannot believe this is really being taught!

0.5 is not equal to 50% just if you assume that it is 0.5 of 1
> 0.5 can be 20% in case of being 0.5 of 2.5
> 0.5 can be any % depending on the base
and exactly this is the bad teaching. A number being integer or decimal is NEVER a portion except you express it explicitly in such context.

This is horrible mathematics for me ...

sorry ;-)

#2 Help Me ! » Is a decimal a percentage "in the US"? » 2015-11-18 05:31:53

Marymo
Replies: 5

Hi everyone,

this morning I became very confuse, together with  my son. We moved to CA 8 months ago and love it, kids are doing great in school. However, in his 6th grade middle school my son is currently learning strange things in math - in my eyes. Is there anybody who could please add more US perspective to my experience?
As they are working with fractions, decimals and percentage, they make a lot of use of changing between theses kind of expressions. In his assessment I just saw the task "change 1.074 to percent" and the right answer would have been 107.4%. This is very awkward to me! Any number -  being integer, natural, rational or even real can be a percentage OF ANOTHER GIVEN AMOUNT but not in itself. And there was no base amount given with the task. The next task was then "change 578.3% to a decimal" and the answer of 5.783 was expected.
To say the truth, I am flattened by this teaching and my son is now quite confused ...

Looking forward to insights!!

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