What is the 8-bit binary representation of decimal 69?

• A. 01000101
• B. 01011010
• C. 00110010
• D. 11001001

Answer: (A)

Understanding decimal to binary conversion means mapping each decimal value to bit positions that represent powers of two. For 69, break it down into the powers of two that sum to it: 64 + 4 + 1. In an 8-bit byte, the bit positions correspond to 128, 64, 32, 16, 8, 4, 2, and 1. Set the bits for 64, 4, and 1 to 1, and the others to 0. This gives 0 1 0 0 0 1 0 1, which is 01000101 in binary. This pattern accurately represents 69 in 8-bit form. Other shown bit patterns correspond to different decimal values (for example, 01011010 is 90, 00110010 is 50, and 11001001 is 197).