帮我看看这句英文怎么理解

题目

帮我看看这句英文怎么理解
Five years later those who had passed in the upper ten per cent all , without exception , had executive positions , while not a single young man of the lower twenty-five per cent had become an executive.（这句话中in the upper ten per cent all是什么意思,上10%?估计不对）

答案

LZ的文字是听写下来的、不是原稿吧?the upper ten per cent all 估计应该是 the upper 10 percentile = 最高的10%