document.write( "Question 1088854: The half-life of Palladium-100 is 4 days. After 20 days a sample of Palladium-100 has been reduced to a mass of 1 mg.\r
\n" ); document.write( "\n" ); document.write( "What was the initial mass (in mg) of the sample? \r
\n" ); document.write( "\n" ); document.write( "What is the mass 5 weeks after the start? \n" ); document.write( "
Algebra.Com's Answer #703221 by jorel1380(3719)\"\" \"About 
You can put this solution on YOUR website!
The formula for exponential decay is P=P(0)e^-kt, where P(0) is the initial population, P is the final population, k is the constant rate of decay, and t is time. Then, in this case:
\n" ); document.write( "P/P(0)=.5=e^-4k
\n" ); document.write( "ln 0.5=ln e^-4k
\n" ); document.write( "-0.69314718055994530941723212145818=-4k
\n" ); document.write( "k=0.17328679513998632735430803036454
\n" ); document.write( "Then, to solve for 1 mg, we hve
\n" ); document.write( "1=P(0)e^-0.173286795(20)
\n" ); document.write( "1=P(0).03125
\n" ); document.write( "P(0)=32
\n" ); document.write( "..........
\n" ); document.write( "5 weeks population:
\n" ); document.write( "P=32*e^-0.17328679513998632735430803036454(35)
\n" ); document.write( "P=0.07432544468767 gms
\n" ); document.write( "☺☺☺☺\r
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