Using proportions, it is found that 32 models are needed.
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This question is solved using proportions, by a rule of three.
1 model - 100 elements
n models - 3200 elements
Applying the cross multiplication
[tex]100n = 3200[/tex]
[tex]n = \frac{3200}{100} = \frac{32}{1} = 32[/tex]
Thus, 32 models are needed.
A similar problem is given at https://brainly.com/question/23536327