What is the missing term in the geometric sequence?

-6,24,?,384,-1536, ...

?=

a.-204

b.-144

c.-96

d.-72

Solution:

formula : an=a1 (r) ^n-1

n - number of term that is unknown

a1 - first term

r - second term divided by the first term

a1=-6

a2=24

a3=?

a4=384

a5=-1536

a3=-6 (24:-6) ^3-1

a3=-6 (-4) ^2

a3=-96

therefore the 3rd term is - 96 (c)