Difficulty: Easy
Correct Answer: Two
Explanation:
Introduction / Context:
Ordering digits and picking positional values is a staple reasoning task. Here, you form a strictly ascending sequence, then index from different ends and compute a numeric difference.
Given Data / Assumptions:
Concept / Approach:
Ascending order for the digits yields a unique sequence. Convert “k-th from right” to an index from the left if helpful (for an 8-digit number, 4th from right = 5th from left).
Step-by-Step Solution:
Verification / Alternative check:
Visual scan from the right: rightmost digits are 9(1st), 8(2nd), 7(3rd), 5(4th) ⇒ still 5. Third from left remains 3.
Why Other Options Are Wrong:
Common Pitfalls:
Forgetting that “from right” reverses the direction; mis-sorting (placing 7 before 5), or missing that there are eight digits.
Final Answer:
Two
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