The reason why Ramadan changes every year in relation to the Gregorian calendar

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Check below answers in case you are looking for other related questions:
Is it permissible for one who is observing i‘tikaaf to leave the mosque in order to wake his family up for sahoor, then come back?
They start fasting one day after the people do so and break the fast one day after the people do so

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Is it permissible for one who is observing i‘tikaaf to leave the mosque in order to wake his family up for sahoor, then come back?
They start fasting one day after the people do so and break the fast one day after the people do so

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