Question

Find the sum of the geometric sequence.
4/3, 8/3, 16/3, 32/3, 64/3

Answer 1

@satellite73 @jim_thompson5910

Answer 2

What's the first term?

What's the common ratio?

Answer 3

4/3

Answer 4

1/2?

Answer 5

@jim_thompson5910

Answer 6

4/3 is the correct first term

Answer 7

1/2 is not the common ratio

Answer 8

1/2 is close though

Answer 9

1/3? hahs

Answer 10

solve for r

(4/3)r = 8/3

Answer 11

2 @jim_thompson5910

Answer 12

good

Answer 13

Now use the formula

\[\Large S_{n} = a*\frac{1-r^n}{1-r}\]

Answer 14

in this case

a = 4/3
r = 2
n = 5

Answer 15

i got -44

Answer 16

that's incorrect

Answer 17

\[\Large S_{n} = a*\frac{1-r^n}{1-r}\]
\[\Large S_{5} = \left(\frac{4}{3}\right)*\frac{1-2^5}{1-2}\]
\[\Large S_{5} = ???\]

Answer 18

-32.6666666667

Answer 19

@jim_thompson5910

Answer 20

that's not correct either

Answer 21

what is 1 - 2^5 ?

Answer 22

-31

Answer 23

1 - 2 = ???

Answer 24

-1

Answer 25

\[\Large S_{n} = a*\frac{1-r^n}{1-r}\]
\[\Large S_{5} = \left(\frac{4}{3}\right)*\frac{1-2^5}{1-2}\]
\[\Large S_{5} = \left(\frac{4}{3}\right)*\frac{-31}{-1}\]
\[\Large S_{5} = ???\]

Answer 26

41.3333333333

Answer 27

or 124/3

Answer 28

Thank you♥

Answer 29

you're welcome