document.write( "Question 1129962: The half-life of a radioactive substance is 50 years. If you start with some amount of this substance, what fraction will remain in 100 years? What fraction will remain in 300 years?\r
\n" ); document.write( "\n" ); document.write( "The fraction that will remain in in 100 years is the following. ______\r
\n" ); document.write( "\n" ); document.write( "The fraction that will remain in in 300 years is the following. ______ \n" ); document.write( "

Algebra.Com's Answer #746588 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

You can put this solution on YOUR website!
The half-life of a radioactive substance is 50 years.
\n" ); document.write( " If you start with some amount of this substance, what fraction will remain in 100 years? What fraction will remain in 300 years?
\n" ); document.write( ":
\n" ); document.write( "The radio active decay formula: A = Ao*2^(-t/h), where
\n" ); document.write( "A = remaining amt after t time
\n" ); document.write( "Ao = initial amt
\n" ); document.write( "t = time of decay
\n" ); document.write( "h = half-life of substance
\n" ); document.write( ":
\n" ); document.write( "let initial amt = 1
\n" ); document.write( "t = 100 yrs
\n" ); document.write( "A = 1*2^(-100/50)
\n" ); document.write( "A = .25
\n" ); document.write( "The fraction that will remain in in 100 years is the following: .25 or $\"1%2F4\"$
\n" ); document.write( ":
\n" ); document.write( "t = 300
\n" ); document.write( "A = 1*2^(-300/50)
\n" ); document.write( "A = .015625
\n" ); document.write( "The fraction that will remain in in 300 years is the following: .015625 or $\"1%2F64\"$ \n" ); document.write( "

\n" );