Answer: 398765
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Work Shown:
x = total number of copies sold so far
8.1% of x = 0.081*x = amount of copies sold in the first month
0.081*x = 32300
x = 32300/0.081
x = 398,765.432098766
x = 398,765
Rounding to the nearest whole number, about 398,765 copies have been sold so far to date.