Answer:
Explanation:
The system is common use is the decimal system which is based on 10;
So for example the number 45 :
45 = 4 * 10^1 + 5 * 10^0 and
132 = 1*10^2 + 3*10^1 + 2*10^0.
The single digits in the decimal system are 0,1,2,3,4,5,6,7,8 and 9 .
Then we have 10, 11 and so on
Then there is the binary system which is based on 2 digits
In this system there are only 2 digits 0 and 1, so
10 binary = 1*2^1 + 0*2*0 which is equivalent to 2 in the decimal system.
111 binary = 1*2^2 + 1*2^1+ 1*2*0 = 4 + 2 + 1 = 7 decimal
Another system is the octal system, based on 8.
The digits are 0,1,2,3,4,5,6,7
So 10 octal = 8 + 0 = 8 decimal
and 17 octal = 1*8^1 + 7* 8^0 = 8 + 7 = 15 decimal.