Answer: 5 inches.
Step-by-step explanation:
Let be "x" the length of the airplane (in inches) in Will's drawing.
The first step to solve this exercise is to find the scale factor.
Since the airplane has a 100 foot wingspan and in his drawing the airplane has a wingspan of 10 inches, you get that the scale factor is:
[tex]scale\ factor=\frac{10}{100}=\frac{1}{10}[/tex]
Finally, knowing the scale factor and knowing that the airplane is 50 feet long, you can multiply this lenght by the scale factor in order to find the length of the airplane (in inches) in Will's drawing.
This is:
[tex]x=(50)(\frac{1}{10})\\\\x=5[/tex]
Its lenght in Will's drawing is 5 inches.
