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Dan read 104 pages of his book. He has 68% of his book left to read. How many pages are in his book?

User Flink
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1 Answer

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The answer is: " 325 pages " .
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Step-by-step 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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User Drom
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