A rhombus has a perimeter of $68$ units and one of its diagonals is $30$ units. What is its area in square units?
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A rhombus has a perimeter of $68$ units and one of its diagonals is $30$ units. What is its area in square units?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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A rhombus has a perimeter of $68$ units and one of its diagonals is $30$ units. What is its area in square units?
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