Chapter 11 - Review - Page 668: 42

25 pounds of decay 175 pounds of decay in the first three years

$a_n = 200*.5^n$ $n=3$ $a_n = 200*.5^n$ $a_3 = 200*.5^3$ $a_3=200*.125$ $a_3=2*12.5$ $a_3=25$ 25 pounds of decay First three years: $n=1$ $a_n = 200*.5^n$ $a_1 = 200*.5^1$ $a_1=200*.5$ $a_1=100$ $n=2$ $a_n = 200*.5^n$ $a_2 = 200*.5^2$ $a_2=200*.25$ $a_2=50$ $100+50+25=175$ 175 pounds of decay in the first three years