Respuesta :

[tex] 24 = 3 \cdot 2^3 [/tex]

[tex]96=3\cdot 2^5 [/tex]

[tex] 384=3\cdot2^7[/tex]

hence it is a geometric progression, with a multiplied constant [tex]3[/tex]

Sum of G.P. of [tex]n[/tex] terms [tex] S_n = a\dfrac{r^n-1}{r-1}\quad \text{where } r \text{ is the common ratio and } a \text{ is the first term} [/tex]

and [tex] r=-2^2=-4[/tex]

Note that the constant should be separated, so

[tex] a= -8 [\tex]

after plugging the values, you'll get the answer

[tex] -26216 \times 3 [/tex]

which option C

Answer:

C

Step-by-step explanation:

-24+96-384+...

a=-24

r=96/(-24)=-4

[tex]s_{7}=a\frac{1-r^7}{1-r} \\=-24\frac{1-(-4)^7}{1-(-4)}\\=-24\frac{1+4^7}{1+4} \\=-24\frac{1+16384}{5} \\=-24\frac{16385}{5} \\=-24 \times 3277\\=-78648[/tex]