Respuesta :

Answer:

The Formula for Percent Proportion is Parts /whole = percent/100. This formula can be used to find the percent of a given ratio and to find the missing value of a part or a whole.

Answer:

a = 9

Step-by-step explanation:

[tex]\frac{4}{12}[/tex] = [tex]\frac{a}{27}[/tex] ( cross- multiply )

12a = 108 ( divide both sides by 12 )

a = 9