She is not sure whether she became pure before Fajr; should she pray and fast?

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Check below answers in case you are looking for other related questions:
She fasted even though she was not sure that her period had ended
Taking pills to prevent period in the last ten days of Ramadaan

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Related Answers:
Her nifaas ended before forty days but she did not pray; does she have to make up the prayers?
She gets a sticky white discharge before her period and a week afterwards
Brownish discharge one day after menses ended
She fasted even though she was not sure that her period had ended
Taking pills to prevent period in the last ten days of Ramadaan

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