Posted by Shay on .
20. Think of a number.
Add 7.
Double the result.
Subtract 8.
Double the result.
Add 12.
Divide by 4.
Subtract 6.
Your answer will be the original number. Explain how this trick works.

Math 213 Elementary Math 
drwls,
If 20 is the answer, what is the question?
20 is not a question