Answer:
C. 64 = 0.80 x n; 80
Step-by-step explanation:
In this context "of" means "times." The given relation can be translated to ...
64 is 80% of what
64 = 0.80 × what
If we let "n" represent the number that would answer "what", then this is ...
64 = 0.80 × n
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Dividing by the coefficient of n, we find the value of n to be ...
64/0.80 = n = 80