If today is October 24th and we observe a waning crescent, on what approximate date did we observe the last waxing crescent?

I believe it is October 1st, October 2rd or October 3rd because it says "approximate date".

Explanation:

Here's Why:

The whole Synodic Period(All Lunar Phases) takes around 29.5 days you can round it to 30 if it's necessary. To know the time for each phase just divide the total amount of days the Synodic Period lasts to finish (29.5) by the amount of phases of the moon(8). The answer is 3.69 days each phase. Now it's common sense and basic math to know when was the last waxing crescent. if the Waning Crescent is on the 24th then count how many phases are between the waning crescent and waxing crescent there should be 6 phases(without counting the original phase, but count the phase you are looking for). So now 3.69 x 6= 22.14 I suggest to round it to 22. And now the basic math part 24-22= 2. Therefore the last waxing crescent was in October 2nd, But, some assignments might make it the 3rd or 1st because it says "approximate date". Hope it Helped

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