document.write( "Question 387320: Use the exponential decay model A=Pe^(kt) to solve the following proublem.
\n" ); document.write( "The half-life of plutonium-238 is days. The initial amount is 100 grams.
\n" ); document.write( "a)find the value of K to four places.
\n" ); document.write( "b) write the formula for the amount of plutonium-238 present at the end of T days.
\n" ); document.write( "c)How much of the initial amount will remain after 30 days? Round the answer to the nearest tenth gram.\r
\n" ); document.write( "\n" ); document.write( "I know this seems like alot but I swear it's all one proublem just has Three parts to it, been having trouble, thank you sooo much in advance!!! :)
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Algebra.Com's Answer #273808 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Use the exponential decay model A=Pe^(kt) to solve the following proublem.
\n" ); document.write( "The half-life of plutonium-238 is days. The initial amount is 100 grams.
\n" ); document.write( "a)find the value of K to four places.
\n" ); document.write( "(1/2)P = P*e^(k*238)
\n" ); document.write( "e^(238k) = 1/2
\n" ); document.write( "Take the natural log of both sides to get:
\n" ); document.write( "238k = ln(1/2)
\n" ); document.write( "k = -0.002912
\n" ); document.write( "---------------------------
\n" ); document.write( "b) write the formula for the amount of plutonium-238 present at the end of T days.
\n" ); document.write( "A(t) = P*e^(-0.002912t)
\n" ); document.write( "---------------------------
\n" ); document.write( "c)How much of the initial amount will remain after 30 days? Round the answer to the nearest tenth gram.
\n" ); document.write( "A(30) = 100*e^(-0.002912*30
\n" ); document.write( "---
\n" ); document.write( "A(30) = 100*0.916337
\n" ); document.write( "A(30) = 91.6337 grams
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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