Question 619019
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Hi
what is the sum of the series of S7 for 5+10+20+40+..
Geometric Series:  r = 2
{{{a[n] = 5(2)^(n-1)}}}
{{{S[n]= a[1]((1-r^n)/(1-r))}}}
{{{S[7]= 5((1-2^7)/(-1))}}} = 635