For an inverse variation, we basically consider a relationship between two values such that, an increase in one results in a decrease in the other one, and vice versa.
This means, for the question provided, the number of days required to build is inversely proportional to the number of workers. The more days spent building, the lesser the number of workers required, and similarly the less days spent building the more number of workers required.
The general formula for an inverse variation is;
Using the values given which are 68 days and 8 workers, we would have;
Therefore, with 17 workers, the number of days would be;
ANSWER:
It would take 32 days