Real-Life Math
Being a cyber detective requires an expert knowledge of computers.
In order to track down hidden information, cyber sleuths may need to translate
computer codes.
"Computers work in binary, which is most often represented
in hexadecimal," says Paul Porter, a computer forensics expert. "These codes
must be translated to understand what they represent. Often tools will be
available to help, but one should understand the tools and the basics."
You
have been hired by the owner of a chemical company to investigate an ex-employee.
The owner thinks the employee took valuable information about a specific customer
account with him when he left.
You want to examine all computer files
related to this customer. To do this, you need to translate the customer's
account number into a code the computer can understand. Instead of giving
the computer a number using the regular number system (which has a base of
10), you need to translate the number into hexadecimal (which has a base of
16).
How do you convert a number from base 10 to hexadecimal? Basically,
you keep dividing the number by 16 until you come up with a remainder that
is less than 16. Let's say that you want to write the number 22 in hexadecimal.
First,
you divide 22 by 16
22 / 16 = 1 with a remainder of 6
The
remainder of 6 goes into the number place farthest to the right. __6
The
number 1 is less than 16, so we can't divide into 16 any more. The number
1 goes in the spot to the left of the 6.
16
In hexadecimal,
the number 22 = 16.
Don't let working in another
base throw you! In the base 10 numeric system, the number 12 simply means
you have 1 quantity of 10 with a remainder of 2. In hexadecimal, 16 represents
1 quantity of 16 with a remainder of 6.
There is one more thing you
need to know. When working in hexadecimal, each place value can contain digits
between 1 and 15. How do you write down a number between 10 and 15 without
using 2 number places? You use letters to represent these numbers: a for 10,
b for 11, c for 12, d for 13, e for 14, and f for 15.
The client wants
you to investigate all files pertaining to customer account number 3,672.
Translate this number into hexadecimal so that the computer can
read it.