For a certain book published by Enlightenment Publishing House, the cost of each book this year has increased by 10% compared to last year, but the original price is still maintained, so the profit per book has dropped by 40%. What is the percentage?
开明出版社出版的某种书，今年每册书的成本比去年增加10%，但是仍保持原售价因此每本利润下降了40%，那么今年这种书的成本在售价中所占的百分数是多少？
<result>0.88</result>