Question

Please help! Will give medal!

What is the sum of a 7-term geometric series if the first term is -11, the last term is -45,056, and the common ratio is -4?

A.) -143,231
B.) -36,047
C.) 144,177
D.) 716,144

Answer 1

Ok I still don't really get it

Answer 2

715,144 would be correct

Answer 3

Thank you!

Answer 4

your welcome

Answer 5

just ask me because i am good at math

Answer 6

Ok @emily.getch what about this one

Answer 7

that would be 2/3

Answer 8

ok and how about this?

Answer 9

it would be A

Answer 10

told you

Answer 11

i got to go

Answer 12

@emily.getch Yayy! Ok last one:

Answer 13

correction formula for \[Sn=a \frac{ r^n-1 }{ r-1 }\]
n=7
a=-11
r=-4
find S7

Answer 14

\[S7=-11\frac{ \left( -4 \right)^7-1 }{ -4-1 }=-11\frac{ -16384-1 }{ -5 }=\frac{ 11*-16385 }{ 5 }=?\]