What time is it 30 degrees west if it's 1 pm at 15 east

Every 15 degrees there's an hour difference. That means that from 15 to 0 there's 15 degrees, and from 0 to 30 west there's twice the 15 which means two hours, which means that there's a three hour difference between the two points.  That means that the time would be 10 am since there's a three hour difference between 10am and 1pm.

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