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Probability Calculator

Calculate the probability of two independent events, combined.

Assumes A and B are independent (one doesn't affect the other) — like two separate coin flips or dice rolls.

Sleep Cycle Calculator

Find the best time to sleep or wake up based on 90-minute cycles.

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Fibonacci Sequence Generator

Generate the Fibonacci sequence up to N terms.

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Perfect Number Checker

Check if a number is a perfect number.

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Armstrong Number Checker

Check if a number is an Armstrong (narcissistic) number.

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Shift Schedule Calculator

Calculate total hours worked across multiple shifts.

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Business Hours Difference Calculator

Calculate working hours between two dates, excluding weekends.

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