1. Divide the number repeatedly by 2:
Keep track of each remainder.
We stop when we get a quotient that is equal to zero.
- division = quotient + remainder;
- 27 042 820 ÷ 2 = 13 521 410 + 0;
- 13 521 410 ÷ 2 = 6 760 705 + 0;
- 6 760 705 ÷ 2 = 3 380 352 + 1;
- 3 380 352 ÷ 2 = 1 690 176 + 0;
- 1 690 176 ÷ 2 = 845 088 + 0;
- 845 088 ÷ 2 = 422 544 + 0;
- 422 544 ÷ 2 = 211 272 + 0;
- 211 272 ÷ 2 = 105 636 + 0;
- 105 636 ÷ 2 = 52 818 + 0;
- 52 818 ÷ 2 = 26 409 + 0;
- 26 409 ÷ 2 = 13 204 + 1;
- 13 204 ÷ 2 = 6 602 + 0;
- 6 602 ÷ 2 = 3 301 + 0;
- 3 301 ÷ 2 = 1 650 + 1;
- 1 650 ÷ 2 = 825 + 0;
- 825 ÷ 2 = 412 + 1;
- 412 ÷ 2 = 206 + 0;
- 206 ÷ 2 = 103 + 0;
- 103 ÷ 2 = 51 + 1;
- 51 ÷ 2 = 25 + 1;
- 25 ÷ 2 = 12 + 1;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 3 ÷ 2 = 1 + 1;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
27 042 820(10) = 1 1001 1100 1010 0100 0000 0100(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 25.
- A signed binary's bit length must be equal to a power of 2, as of:
- 21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32; 26 = 64; ...
- The first bit (the leftmost) indicates the sign:
- 0 = positive integer number, 1 = negative integer number
The least number that is:
1) a power of 2
2) and is larger than the actual length, 25,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 32.
4. Get the positive binary computer representation on 32 bits (4 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 32.
Decimal Number 27 042 820(10) converted to signed binary in two's complement representation:
Spaces were used to group digits: for binary, by 4, for decimal, by 3.