show the bit configuration of a 24bit register which its contents represents
the decimal number of 295 in binary code??????????

i dont know where to start this thing

what stuff should i read in order to know how to solve this stuff
???

 

Give these a try:

http://www.allaboutcircuits.com/vol_4/chpt_1/6.html

or

http://www.wikihow.com/Convert-from-Decimal-to-Binary