To get ready for the new school year, Mary brought her two kids shopping. She bought her son James, a coat for $40 and two pairs of jeans. She bought his sister Jamie, a pair of shoes for $30. The total cost of the items was $110. If the two pairs of jeans for James cost the same price, how much did one pair of jeans cost?
Please reason step by step, and put your final answer within \boxed{}.
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