document.write( "Question 1163332: You go to the doctor and he gives you 13 milligrams of radioactive dye. After 24 minutes, 6 milligrams of dye remain in your system. To leave the doctor's office, you must pass through a radiation detector without sounding the alarm. If the detector will sound the alarm if more than 2 milligrams of the dye are in your system, how long will your visit to the doctor take, assuming you were given the dye as soon as you arrived? Give your answer to the nearest minute. \n" ); document.write( "
Algebra.Com's Answer #787398 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Radioactive decay conforms to the exponential model where is the initial amount, is the growth/decay constant, and is the elapsed time.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Since the initial amount was 13 mg we have the initial expression:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "But then we are given:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Solving for the constant of decay:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Once you have done the arithmetic to find the value of you can write the full function for your particular situation:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Insert the value of the constant and then set the function equal to 2 mg and solve for minutes.
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "John
\n" ); document.write( "
\n" ); document.write( "My calculator said it, I believe it, that settles it
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" );