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a 29 gram sample of a substance that's used to preserve fruits and vegetables has a k-value of 0.1359. Find the substance's half life in days. Round to nearest tenth

2 Answers

5 votes

for plato the answer is 5.1!!

User Daniele Torino
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3 votes
okay well
a(t)= amount of substance remaining after t days
assuming exponential decay, a(t)=29e^-0.1359t

now, find the half, set a(t)= half the original and solve for t

14.5=29e^-0.1359t
0.5=e^-0.1359t
In(0.5)=In(e^-0.1359t)
In(0.5)=-o.1359t

t=in(0.5)/(-0.1359)= (aprox) 5.1 days

User Spons
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