If you want to give yourself a way to practice and then check your
answers, many calculators will do some conversions for you.
In particular, the standard calculator application that comes as part
of Windows will convert numbers between decimal, binary, octal or
hexadecimal. This calculator can usually be started by looking in the
Start -> Programs -> Accessories menu. When it begins, it
generally looks like a very simple calculator. However, there is a
menu title "View" at the top of the calculator that lets you select
between "Standard" and "Scientific" views. Select the Scientific
view.
In scientific mode, you will see a box that allows you to pick between
one of four number systems: Hex(adecimal), Dec(imal), Oct(al), or
Bin(ary). If you want it to convert from decimal to binary, select
decimal mode, then type in a decimal number, then click on binary
mode. In the same way you can convert from binary to octal, and so
on. You can also perform all of the arithmetic operations while
working in any of the number systems. Please note, however, that this
calculator does not handle fractional values in any base other than decimal.
One warning: When working outside of decimal notation, the calculator
can only handle values which fit in 32 bits or less (limit is
slightly less than 4.3 billion). Also, I strongly recommend that you
keep the selection on the right as "Dword" when working in one of the
other bases.