What is the BCD code for decimal digit 3?
0011
This question tests BCD (Binary Coded Decimal) encoding. In BCD, each individual decimal digit from 0 to 9 is represented by its own 4-bit binary group using the standard 8-4-2-1 positional weights. Because a 4-bit field can hold values 0–15 but only 0–9 are valid decimal digits, the six combinations 1010 through 1111 are invalid/unused in BCD.
To find the code for decimal 3, convert 3 to 4-bit binary using the place values 8, 4, 2, 1:
- 8 → 0, 4 → 0, 2 → 1, 1 → 1
- 3 = 2 + 1 = 21 + 20 = 0011
So the BCD code for decimal 3 is 0011, the correct answer. A short reference:
| Decimal | BCD |
|---|---|
| 1 | 0001 |
| 2 | 0010 |
| 3 | 0011 |
| 5 | 0101 |
| 6 | 0110 |
Why the other options are wrong:
- 0001 is the code for decimal 1 (weight 1 only).
- 0101 equals 4 + 1 = 5, so it is the code for decimal 5.
- 0110 equals 4 + 2 = 6, so it is the code for decimal 6.
Important Questions from Binary Codes
- What is maximum number represented by 4 bit BCD code?
The number of bytes required to represent the decimal number 1856357 in packed BCD (Binary Coded Decimal) form is ________.
Which of the following is an invalid state in 8-4-2-1 Binary Coded Decimal counter
Digital calculators use __________.
The number of bits used to store a BCD digit is
