In a simple letter to number code, each letter of the English alphabet is replaced by its position in the alphabet, that is, A is coded as 1, B as 2, C as 3 and so on. Using this rule, how is the word BIDDIC coded as a sequence of digits?

Introduction / Context:
This question uses the most straightforward form of letter to number coding, where each uppercase English letter is replaced by its position in the alphabet. This is a standard coding scheme used in many reasoning questions and is easy to remember once you are familiar with alphabetical order. We are asked to convert the word BIDDIC into the corresponding six digit code by replacing each letter with its numerical position and writing the digits together in order.

Given Data / Assumptions:

• The English alphabet is considered in the usual order from A to Z.
• Each letter is coded as its position: A = 1, B = 2, C = 3, and so on up to Z = 26.
• The word to be coded is BIDDIC.
• We must write the code as a sequence of digits without spaces between the letters.

Concept / Approach:
The process is mechanical. First we recall or quickly list the positions of the relevant letters in the alphabet. Then we replace each letter in the word with its corresponding number. Finally, we concatenate these numbers in the same order to form the final code. Since the mapping is one to one and very simple, accuracy mainly depends on remembering the correct alphabetical positions and avoiding transposition of digits when writing the sequence.

Step-by-Step Solution:
Step 1: Identify the letters of the word in order: B, I, D, D, I, C. Step 2: Find the alphabetical position of each letter. B is the second letter, so B = 2. Step 3: I is the ninth letter, so I = 9. Step 4: D is the fourth letter, so D = 4. The word has D twice in the middle, so both positions will be 4. Step 5: The second I again corresponds to 9, and C is the third letter, so C = 3. Step 6: Write the digits together in order: B I D D I C becomes 2 9 4 4 9 3. Step 7: The final code is therefore 294493.

Verification / Alternative check:
We can quickly verify by comparing with the alphabet. The sequence A, B, C, D, E, F, G, H, I shows that B is 2, C is 3, D is 4 and I is 9. This confirms that our digit substitutions are correct. As a further check, we can look at the options and confirm that only one option exactly matches 2 9 4 4 9 3 without any digit swapped or altered. This gives us additional confidence in the answer.

Why Other Options Are Wrong:
Option 284483 incorrectly assigns 8 to the first I or changes one of the D positions. Option 294483 changes one of the central 4 digits to 8. Option 294439 and 214493 similarly misplace or alter one or more digits. None of these sequences correspond exactly to the correct letter positions B = 2, I = 9, D = 4, D = 4, I = 9, C = 3. Therefore they do not represent the true code of BIDDIC under the given scheme.

Common Pitfalls:
The most common error is misremembering one of the positions, especially for letters around the middle of the alphabet. Another mistake is to accidentally swap the order of digits when writing the code or to miscount the number of repeated letters. To avoid such issues in an exam, it helps to practise the positions of letters or to mentally anchor a few key letters such as A, M and Z and count relative to them. Careful writing of the digits in the correct sequence also prevents avoidable mistakes.

Final Answer:
Using the rule A = 1, B = 2, C = 3 and so on, the word BIDDIC is coded as 294493.