Respuesta :

The answer is:  " 325 pages " .
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Explanation:
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100%  −  68%  =  32% .

So, 104 pages is 32% of the book.
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So the question is:
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       " 32% of what number (= number of pages in book) is "104" ?
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   32% = 32/100 = 32 ÷ 100 = 0.32  .
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      (0.32)x = 104 ;   Divide EACH SIDE of the equation by:  "(0.32)" ; to isolate "x" on one side of the equation; and to solve for "x" ;
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     [(0.32)x] / (0.32) = 104 / (0.32) 

                          x = 325 pages .
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Alternate: 

" 32% of what number (= number of pages in book) is "104" ?

32% = 32/100 ;  

32x / 100 = 104 ; 

32x = (104)* (100) ; 

32x = 10,400  ;

      Divide EACH SIDE by "32" ; to isolate "x" on each side of the equation; and to solve for "x" ; 

32x / 32  = 10,400 / 32  ;

       x = 325 pages .
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