Answer:
279
Explanation:
496*1/4=124 496/8=62 496/16=31 124+62+31=217 496-217=279
we have 496 books
primary students 496*1/4=124 books
intermediate students 496*1/8=62 books
upper students 496*1/16=31 books
teachers bought 496-(124+62+31)=279 books
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