Question 1077705
half the mass lost in 16 hours is (1/2)=e^(-16k)
-ln2=-16k
k=ln2/16=0.04332 for X
k=ln2/21=0.03301 for Y
We want e^(-0.04332t)/e^(-0.03301t)=1/3
3e^(-0.04332t)=e^(-0.03301t)
do ln both sides
ln3-0.04332t=-0.03301t
ln3=0.01031t
t=106.56 hours
In that time, X will have 3e^(-4.616)=0.02967 kg
Y will have 3e^(-3.517)=0.0890 kg
That ratio is 3.00 to 1.