Question

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?

Answer 1

a) -143,231
b) -36,047
c) 144,177
d) 716,144

Answer 2

What is the formula?

Answer 3

umm? idk.

Answer 4

I don't know either. I could look it up. Why don't you look up the formula for the sum of a geometric sequence?

Answer 5

im trying but i dont really know what to look for

Answer 6

copy and paste this in a google search bar: sum of geometric sequence

Answer 7

Did you find it yet?

Answer 8

no

Answer 9

im looking but i dont know what it is i have no clue

Answer 10

http://www.regentsprep.org/Regents/math/algtrig/ATP2/GeoSeq.htm