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ankoles [38]
4 years ago
14

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
Mathematics
2 answers:
kaheart [24]4 years ago
6 0
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

Aleksandr [31]4 years ago
5 0

for plato the answer is 5.1!!

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Here is the link to the spreadsheet with standard deviation calculation:
https://docs.google.com/spreadsheets/d/1pnsJIrM_lmQKAGRJvduiHzjg9mYvLgpsCqCoGYvR5Us/edit?usp=sharing
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