In the number 76534218, each digit is replaced by the next higher digit (for example 1 becomes 2, 2 becomes 3 and so on) and then all the new digits are arranged in ascending order from left to right. Which digit will be fifth from the left end in the final arrangement?

Introduction / Context:
This reasoning question checks your ability to handle digit manipulation and ordering. You first perform a transformation on each digit, then sort the resulting digits. Such problems are common in aptitude tests because they combine two skills: understanding a simple mapping on digits and then correctly arranging numbers in ascending order. Careful step-by-step work avoids errors.

Given Data / Assumptions:

• The original number is 76534218.
• Each digit is replaced by the next higher digit: 1 becomes 2, 2 becomes 3, 3 becomes 4, and so on, up to 9.
• After replacement, all new digits are arranged in ascending order from left to right.
• We need the digit that appears at the fifth position from the left in the final sorted sequence.

Concept / Approach:
The approach has two phases. First, apply the digit transformation consistently: every original digit d is mapped to d + 1. Second, collect all transformed digits and sort them from smallest to largest. Since there are eight digits, the fifth from the left is the fifth smallest transformed digit. Working systematically ensures that none of the digits are missed or miscopied and that sorting is done correctly.

Step-by-Step Solution:
Write the original digits of 76534218 as a list: 7, 6, 5, 3, 4, 2, 1, 8. Apply the rule “replace each digit by the next higher digit” to each one: 7 becomes 8, 6 becomes 7, 5 becomes 6, 3 becomes 4, 4 becomes 5, 2 becomes 3, 1 becomes 2, and 8 becomes 9. The transformed list of digits is therefore: 8, 7, 6, 4, 5, 3, 2, 9. Now arrange these digits in ascending order: 2, 3, 4, 5, 6, 7, 8, 9. Count from the left. The first digit is 2, second is 3, third is 4, fourth is 5, and the fifth is 6. Thus, the digit at the fifth position from the left in the final arrangement is 6.

Verification / Alternative check:
An alternative quick check is to ensure that all digits from 2 to 9 appear exactly once in the transformed list, because the original digits 1 to 8 all shift up by 1. This means the sorted sequence must be 2, 3, 4, 5, 6, 7, 8, 9. Counting to the fifth position again gives 6. Since this method does not depend on any particular digit being misread, it confirms that the earlier transformation and sorting are correct.

Why Other Options Are Wrong:
Option 4 would be the third digit, not the fifth. Option 5 is the fourth digit in the sorted list. Options 7 and 8 are the sixth and seventh digits respectively. All these are correct digits from the sequence but at different positions. Only the digit 6 occupies the fifth place from the left in the final arrangement.

Common Pitfalls:
A frequent error is to misapply the rule and, for example, treat 9 as wrapping around to 0, which is not stated. Another mistake is failing to transform all digits before sorting, or accidentally sorting the original digits instead of the transformed ones. Some candidates also miscount positions, especially when in a hurry. Always write the full sorted list and then count carefully from the left to avoid such mistakes.

Final Answer:
The digit that will be fifth from the left end in the final ascending arrangement is 6.