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
She thought that the bleeding that results from an abortion was nifaas so she broke her fast

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Related Answers:
She mistakenly thought that her period had finished; she did ghusl and had intercourse with her husband, then more blood came
Brownish discharge that appears before menses
She is asking how she can teach her mother and sister about the rulings on tahaarah (purification)
She fasted even though she was not sure that her period had ended
She thought that the bleeding that results from an abortion was nifaas so she broke her fast

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