<PRE><B>Question 1136373</B>
P=Ab^t, t is hours and P is total and A is beginning
720=360*b^2
b^2=2
b= sqrt (2)=1.414.  P=360* sqrt(2)^t

After 9 hours  it would be 360*b^9=8134.81 or 8135.
To reach 2880, this would be doubling three times so a little fewer than 6 hours to reach 2810
Mathematically, 2810=360*sqrt(2)^n
7.81=sqrt(2)^n
ln both sides
2.05=n *0.3466
rounding at end 5.93 hours.


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