Answer:
The length of the model is 21 inches
Step-by-step explanation:
we have
The scale factor
[tex]\frac{1}{12}[/tex]
That means
1 unit in the model represent 12 units in the actual
1 inch in the model represent 12 inches in the actual
Remember that
[tex]1\ ft=12\ in[/tex]
so
1 inch in the model represent 1 ft in the actual
The scale factor is
[tex]\frac{1}{1}\ \frac{in}{ft}[/tex]
therefore
21 ft in the actual represent 21 inches in the model
