Difficulty: Easy
Correct Answer: 44 times
Explanation:
Problem restatement
Count the number of 90° configurations between the hour and minute hands in 24 hours.
Given data
Concept/Approach
Right angles occur twice in most hours, except slightly irregular spacing due to the hour-hand motion. The well-known count is 22 in 12 hours.
Step-by-Step reasoning
Right angles in 12 hours = 22Hence in 24 hours = 2 × 22 = 44
Common pitfalls
Assuming exactly two per hour (would give 48) and ignoring the skipped/shifted occurrences.
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