Question

Consider the following weights in the BCD code. \[ (i)\;4 \qquad (ii)\;8 \qquad (iii)\;1 \qquad (iv)\;2 \] Find the correct sequence from left to right.

• A. (iv), (i), (ii), (iii)
• B. (iii), (iv), (i), (ii)
• C. (ii), (i), (iv), (iii)
• D. (i), (ii), (iii), (iv)

Hint:

Always remember the standard BCD weight: \[ 8421 \] This is one of the most frequently asked coding-system questions.

Answer 1

The Correct Option is C

Concept: BCD stands for: \[ \text{Binary Coded Decimal} \] The most common BCD code is the 8421 weighted code. Each bit position has a fixed weight.

Step 1: Recall the BCD weights.
In standard BCD: \[ 8 \quad 4 \quad 2 \quad 1 \] These weights are assigned from left to right.

Step 2: Match the given labels.
The question provides: \[ (i)=4 \] \[ (ii)=8 \] \[ (iii)=1 \] \[ (iv)=2 \]

Step 3: Arrange according to 8421 sequence.
BCD order: \[ 8 \rightarrow 4 \rightarrow 2 \rightarrow 1 \] Corresponding labels: \[ (ii)\rightarrow(i)\rightarrow(iv)\rightarrow(iii) \] Therefore, \[ \boxed{(ii),(i),(iv),(iii)} \] Hence, option (C) is correct.