Question

Fill in the blank with the correct form of the ordinal number in parenthesis.

Answer 1

 i believe it is decimo

Answer 2

The correct answer is:  [C]:  "décimo" .
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Don't forget the accent mark.

Note:  The noun—"el piso"— is singular and masculine; hence, the correct answer is:  
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Answer choice:  [C]:  "décimo" .
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Choice [A]:  "décima" ; would refer to a noun that is singular and feminine.
   So;  rule out this option.
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Choice [B]:  "décimos" ; would refer to a noun that is plural and masculine; OR: a noun that is plural, AND (a mixture of at least one masculine AND one or more feminine). 
   So; rule out this option.
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Choice [D]:  "décimas" ; would refer to a noun that is plural and feminine.
   So; rule out this option.
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Answer choice:  [C]:  "décimo" ; would refer to a noun that is singular and masculine;  which is the correct answer choice.
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