Answer:
2.5 inches
Explanation:
To solve for the width, we can write a proportion comparing the original and reduced dimensions. Let w be the width of the model. So:
![(40)/(20)=(5)/(w)](https://img.qammunity.org/2021/formulas/mathematics/college/wgao4fzp7bog9sthjf52q8f2o86w2bkwfe.png)
The left proportion represents the original length to width ratio. The right proportion represent the length to width ratio of the model. We can solve for w by cross multiplying.
First, let's reduce the fraction on the left:
![(2)/(1)=(5)/(w)](https://img.qammunity.org/2021/formulas/mathematics/college/z18xsy51nt7xx7kplzp42hff6szn7vfger.png)
Cross multiply:
![5=2w](https://img.qammunity.org/2021/formulas/mathematics/college/lob2sigmb8c4inqe4b2v3v86zx69qkrpgf.png)
Divide both sides by 2:
![w=5/2=2.5](https://img.qammunity.org/2021/formulas/mathematics/college/mxcvqv85tovpb1mhog0s4ox88f38twk5qp.png)
So, the width of the model is 2.5 inches.
And we're done!