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This was the question:

A reader in China asked about how to change fractions...not just simple ones, into percent.

"I am trying to assist my 6th grader and my way of doing math works, but it appears complicated when I explain it...."

Professor Homunculus' answer:

I know what you mean. I used to be a math teacher, and I understand that each child needs his own method of explanation. There is no "one right way," but I have learned that there is a need for at least one simple, core explanation (a sort of "summary" or "schematic" explanation) that each teacher can build on.

So for how to change fractions into percent, I have come up with this:

A fraction is another way to say "a division problem that hasn't been done yet." Once you have done it, you will get a decimal. So...

• do the division problem to get the decimal.
• Now change the decimal into a percent (which is a lot easier).
  To do that, just make sure you move the decimal point over two places to the right, an stick a % sign behind the whole shebang.
• If there is a mixed fraction, the whole number becomes that many hundred percents. Add the however-many-hundred percents to whatever percent the fraction comes out to be.
  
  Let me explain that last part:
  A whole number (say, the number 1) is 100% (because if you have a one whole cookie, for example, you have 100% of that cookie). The number 3 would be 300%, the number 5 would be 500%, etc.
  So you add the however-many-hundred percents to whatever percent the fraction comes out to be.

The mixed fraction example near the bottom of this page will make that clearer.

Example:

3/4

• Divide 4 into 3 and get .75
• Move the decimal point over two places to the right and get 75%

Another:

7/8

• Divide 8 into 7 and get .875
• Move the decimal point over two places to the right and get 87.5%

Example of a mixed fraction:

5 5/8

• 5 = 500% (that was easy!)
• 5/8 = 8 divided by 5 = .625
• Move the decimal point over two places to the right and get 62.5%
  500% + 62.5% = 562.5%

I hope that helped,

Brian Foley (a.k.a. Professor Homunculus )