Question

find the sum of this geometric series

Answer 1

i got 315 , but thats only if its n-1

Answer 2

5(2^2+2^3+2^4+2^5+2^6+2^7)

Answer 3

=1260

Answer 4

http://www.wolframalpha.com/input/?i=sumation+from+1+to+6+of+5*2%5E%28n%2B1%29 if you would like to check you answers.