The idea of the percentage, numbers out of 100, okay, percent, something - 10 percent, that sort of thing, okay.百分比这一概念表示的是一个数是另一个数的百分之几，比如，10%这种。

So, this is to do with statistics and figures.也就是说，这个概念是与统计数字有关的。You might find it useful if you're taking the IELTS exam or any other exam如果你正在参加雅思考试或其他考试——无论什么考试，where they give you some figures and some percentages and you have to write something about them in one of the tests, okay?