Question

What is the sum of a 6-term geometric series if the first term is 22 and the last term is 1,299,078?

Answer 1

1,395,030
1,461,460
1,527,890
1,594,320

Answer 2

@mathmate

Answer 3

\[S(n)=a(1-r^n)/(1-r)\]
\[ar ^{n-1}\]
\[ar^5\]
\[22r^5=1,299,078\]\[r=(1,299,078/22)^{1/5}=9\]
\[S(6)=22(1-9^6)/(1-9)\]

Answer 4

@Abmon98 has shown all the work. There is nothing left to do except use the calculator to find the numerical answer, which is one of the choices.