document.write( "Question 1129817: The half-life of Erbium-171 is 7.5 hours. What is the hourly decay rate? Express the result to four decimal places.
\n" ); document.write( "Express the hourly decay rate as a percentage to two decimal places.
\n" ); document.write( "Here is how I found the hourly decay rate for the first question:
\n" ); document.write( "ln(1/2)= ln(2)=ln(e^7.5)
\n" ); document.write( "-ln(2)=7.5k
\n" ); document.write( "K=- ln(2)/7.5
\n" ); document.write( "K=-0.0924\r
\n" ); document.write( "\n" ); document.write( "When I’ve gone to figure out the second portion it is incorrect. \n" ); document.write( "

Algebra.Com's Answer #746447 by MathTherapy(10556) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "The half-life of Erbium-171 is 7.5 hours. What is the hourly decay rate? Express the result to four decimal places.
\n" ); document.write( "Express the hourly decay rate as a percentage to two decimal places.
\n" ); document.write( "Here is how I found the hourly decay rate for the first question:
\n" ); document.write( "ln(1/2)= ln(2)=ln(e^7.5)
\n" ); document.write( "-ln(2)=7.5k
\n" ); document.write( "K=- ln(2)/7.5
\n" ); document.write( "K=-0.0924\r
\n" ); document.write( "\n" ); document.write( "When I’ve gone to figure out the second portion it is incorrect.
\n" ); document.write( "

You're CORRECT! k, or hourly decay rate is indeed: - .0924 (to 4 decimal places). Good job!
\n" );
document.write( "Now, all you have to do is MULTIPLY - .0924 by 100, which involves just moving the decimal point 2 places to the right of - .0924, to get: - 9.24% \n" );
document.write( "

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