Explanation

Use the Rate Pie to organize your work. For the first 5 weeks, Noah’s company builds 1 mile per week. Therefore, they build 5 miles of road before the start of the rainy season. Once rainy season begins, they have 6 miles of road left to build. This number is the “work,” and goes in the top of the rate pie.

The rate, $\frac{1}{2}$ miles per week, goes in the lower left segment of the rate pie. Divide 6 by , and you’ll get the total amount of time, or 12 weeks, at that rate.
Therefore, it will take a total of 17 weeks for Noah’s company to build the road.