If he starts fasting with a country that uses calculations, should he break the fast with them?

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Check below answers in case you are looking for other related questions:
Should he follow the local people with regard to starting and ending the fast?
Can Muslims living in Western countries form committees to sight the moon?

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Related Answers:
There is nothing wrong with using modern equipment to sight the moon
If there is an error in the moon sighting, and it is proven that we did not fast on one day of Ramadan, do we have to make it up?
He travelled during Ramadaan to a country where the people started Ramadaan on a different day
Should he follow the local people with regard to starting and ending the fast?
Can Muslims living in Western countries form committees to sight the moon?

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