Question 1027560
To do this, we wish to find the time t, where y = 82, so
y=200(1/2)^t/15
82=200(1/2)^t/15
.41 = (1/2)^t/15
ln .41 = (t/15)ln(1/2)
-.8916 = (t/15)*-.6931
t/15 = 1.2863
t = 19.3 years