Respuesta :

sqdancefan

Answer:

  21 in

Step-by-step explanation:

It can be helpful to realize that the scale is ...

  model : actual = 1 : 12 = 1 in : 12 in = 1 in : 1 ft

Then the actual 21 ft shark will have a model that is 21 inches long.

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  1 in : 1 ft = 21 in : 21 ft