Answer:
see the procedure
Explanation:
we know that
The scale factor of the model is 1/30
That means ----> 1 unit in the model represent 30 units in the actual
so
using proportion
Find out how much represent 5 ft in the model
Convert feet to inches
Remember that
![1\ ft=12\ in](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ctrggs12lsjsw7krei553t526wvg2rr86g.png)
so
![5\ ft=5(12)=60\ in](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4dv3hz7gua8v0zjllnw5okm358kdeqjk27.png)
Let
x -----> the diameter of the circular window in the model house in inches
![(1)/(30)=(x)/(60)\\\\x=(60)/(30)\ in](https://img.qammunity.org/2020/formulas/mathematics/middle-school/e0w385w2gwmbboryw1c50m1t9axtyfcvzw.png)
Simplify
![2\ in](https://img.qammunity.org/2020/formulas/mathematics/middle-school/w637tj2cdjlqc22fmmccbhyjzxhvrjf5ad.png)
therefore
The diameter of the circular window in the model house is 2 inches
see the attached figure to better understand the problem