The weighted average unit cost after the October 22 purchase is $13.70.
The weighted average unit cost determines the weighted average cost of all the purchased inventory.
[(300 x 12) + (390 x 15) ] / (300 + 390)
(3600 + 5850) / 690 = $13.70
To learn more about the weighted average method, please check: https://brainly.com/question/28018617
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