document.write( "Question 916506: Any help with this homework question? Not sure of the formula. Thank you!\r
\n" ); document.write( "\n" ); document.write( "\"The amount of a sample of a radioactive substance remaining after t years is given by a function of the form Q(t) = Q0e^-0.0001t. At the end of 5,000 years, 50 grams of the substance remain. How many grams were present initially? Round your answer to the nearest hundredth gram.\" \n" ); document.write( "
Algebra.Com's Answer #556093 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
let f = q(t)
\n" ); document.write( "let p = q(0)\r
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\n" ); document.write( "\n" ); document.write( "your equation becomes:
\n" ); document.write( "f=p*e^(-.0001*t)\r
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\n" ); document.write( "\n" ); document.write( "replace f with 50 and t with 5000 to get:
\n" ); document.write( "50 = p*e^(-.0001*5000)\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by e^(-.0001*5000) to get:
\n" ); document.write( "50/e^(-.0001*5000) = p
\n" ); document.write( "use your calculator to solve for p to get:
\n" ); document.write( "p = 82.43606354 which you can round as desired.\r
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\n" ); document.write( "\n" ); document.write( "confirm by replacing p with 82.43606354 in the original equation to get:
\n" ); document.write( "f = p*e^(-.0001*5000) becomes:
\n" ); document.write( "50 = 82.43606354*e^(-.0001*5000) which becomes:
\n" ); document.write( "50 = 50\r
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\n" ); document.write( "\n" ); document.write( "this confirms the solution is good.
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