How do you convert 11010101 to decimal?

Answer 1

You multiply the right-most digit by 1, the second from the right by 2, the third by 4, the next by 8, etc., and add everything up:

1 x 1

0 x 2

1 x 4

0 x 8

1 x 16

etc.

Or you use the Windows Calculator in scientific mode. If you are practicing binary, you should do this anyway, to verify the results you get on pencil and paper.

Answer 2

To convert the binary number 11010101 to decimal, you need to multiply each digit by 2 raised to the power of its position from right to left, starting at 0. In this case, the calculation would be: (1 x 2^7) + (1 x 2^6) + (0 x 2^5) + (1 x 2^4) + (0 x 2^3) + (1 x 2^2) + (0 x 2^1) + (1 x 2^0). This simplifies to: 128 + 64 + 0 + 16 + 0 + 4 + 0 + 1, which equals 213 in decimal.