Wheels rotating on a shared axis make 15, 20, and 48 revolutions per minute respectively. Starting from a downward alignment, after what time interval will they realign?
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Answer: A. 1 min
Explanation
The time required for rotating wheels to realign is found by calculating the least common multiple of their frequencies. The rotation frequencies given are fifteen, twenty, and forty eight revolutions per minute respectively. The least common multiple of these rotational frequencies corresponds to a time interval of exactly one minute. Rotational frequency measures the number of complete revolutions an object completes within a fixed time duration. Finding the least common multiple of periodic frequencies determines when separate cycles synchronize and align together. One minute contains sixty seconds, serving as the standard baseline time unit for revolutions per minute calculations.
Two minutes exceeds the minimum time interval required for the rotational frequencies to synchronize completely. Three minutes is unnecessarily long because the wheels achieve full angular realignment much sooner. None of these is incorrect because the first option provides the correct mathematical answer to the problem.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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