Let d represent number of days and n represent number of workers.
We have been given that when building a house, the number of days required to build varies inversely with with the number of workers.
We know that the equation
represents the relation where y is inversely proportional to x and k is the constant of proportionality.
So our required equation would be ![d=\frac{k}{n}](https://tex.z-dn.net/?f=d%3D%5Cfrac%7Bk%7D%7Bn%7D)
Upon substituting our given values, we will get:
![19=\frac{k}{35}](https://tex.z-dn.net/?f=19%3D%5Cfrac%7Bk%7D%7B35%7D)
![k=19\cdot 35](https://tex.z-dn.net/?f=k%3D19%5Ccdot%2035)
![k=665](https://tex.z-dn.net/?f=k%3D665)
Since constant of proportionality is 665, so our equation would be
.
To find the number of days it will take to build a similar house with 5 workers, we will substitute
in our equation as:
![d=\frac{665}{5}](https://tex.z-dn.net/?f=d%3D%5Cfrac%7B665%7D%7B5%7D)
![d=133](https://tex.z-dn.net/?f=d%3D133)
Therefore, it will take 133 days for 5 workers to build a similar house.