A highway is completed in one week, and three-seventh of the highway is completed in three days, right?

wrong

Analysis:

If you repair the same amount every day on average, then it is right;

If the daily maintenance time is different, that is to say, the average maintenance time is different, then it is wrong.

Because it is not clear in the topic whether the average daily length is the same, it can only be judged as an error.