document.write( "Question 844689: A scientist has 100 grams of a substance where half of it decays every hour. Write an equation to determine how long it takes until 25 grams are remaining \n" ); document.write( "

Algebra.Com's Answer #508878 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "Q(t) = 
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document.write( "first find k
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document.write( " .5 = 
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document.write( " ln(.5)/-1 = k = .6931
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document.write( "25 = 
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document.write( " .25 = 
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document.write( "  = t
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document.write( "  \n" );
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