Answers:
a) 80% nonfiction
b) 1200 fiction, 4800 nonfiction
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Step-by-step explanation:
part (a)
We only have two choices: fiction or nonfiction
If 20% are fiction, then 100% - 20% = 80% are nonfiction.
The two percentages 20% and 80% add to 100% to represent all the books.
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part (b)
20% = 20/100 = 0.20
20% of 6000 = 0.20*6000 = 1200
we have 1200 fiction books
6000-1200 = 4800
and we have 4800 nonfiction books
Note how
80% of 6000 = 0.80*6000 = 4800
which helps confirm part (a)