KöMaL 2007 K115

When more than one files are selected on the computer for copying at the same time, and the process of copying is started, there are two progress bars displayed. The upper one shows what percentage of the file just being copied is done and the lower one shows what percentage of the whole copying task is done (including the files copied before the current file). Suppose there are three files copied in this way. When the first file is being copied and the upper progress bar reads 35%, the lower bar reads 14%. When the upper bar reads 24% during the copying of the second file, the lower bar reads 46%. What does the upper progress bar read when the lower one reads 72%? (The given data are exact values, not approximations.)