yay, geometric sum
an=8(2)^(r-1)
anyway, sum of geometric sequence where a1=first term and n=which one and r=common ratio is
[tex]S_n=\frac{a_1(1-r^n)}{1-r}[/tex]
so
first term is 50
common ratio is 2
n=8
[tex]S_8=\frac{50(1-2^8)}{1-2}[/tex]
[tex]S_8=\frac{50(1-256)}{-1}[/tex]
[tex]S_8=-50(-255)[/tex]
S8=12760 visitors in first 8 weeks
