- = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( )
% < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9
( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8
9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7
8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6
7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5
6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3
34
C CHECKING HECKING
YYOUR ANSWERSOUR ANSWERS
What would it be like if you always found the right answer to every
math problem? Imagine scoring 100% on every math test. How
would you like to get a reputation for never making a mistake? If
you do make a mistake, I can teach you how to fi nd and correct it
before anyone (including your teacher) knows anything about it.
When I was young, I often made mistakes in my calculations. I
knew how to do the problems, but I still got the wrong answer. I
would forget to carry a number, or fi nd the right answer but write
down something diff erent, and who knows what other mistakes I
would make.
I had some simple methods for checking answers I had devised
myself, but they weren’t very good. Th ey would confi rm maybe the
last digit of the answer or they would show me that the answer I got
was at least close to the real answer. I wish I had known then the
method I am going to show you now. Everyone would have thought
I was a genius if I had known this.
CChapter 5hapter 5
- = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( )
brent
(Brent)
#1