+29 If the daily exponential decay is 3%, how many days will it take for the amount to be reduced to 4% of the original?
+118609 If the daily exponential decay is 3%, how many days will it take for the amount to be reduced to 4% of the original?
Hi Saintcyr :)
let the initial amount be X, let n be the number of days that have past.
end of day n A=X*0.97^n
When will A=0.04X
0.04X=X*0.97^n
0.04 = 0.96^n
log 0.04 = log 0.97^n
log 0.04 = nlog 0.97
n=log0.04/log0.97
n=105.7
so after 105.7 days there will be 4% remaining
so after 106 days there will be less than 4% remaining.
