Question

Please Help Me!! Will Medal!!

Which two geometric sequences in the following list have the same ratio?

Check all that apply.

A. 5, 20, 80, 320, 1280, ...
B. -4.8, -14.4, -43.2, -129.6, -388.8, ...
C. 6.8, 23.8, 83.3, 291.55, 1020.425, ...
D. 4.3, 17.2, 68.8, 275.2, 1100.8, ...
E. 5, -15, 45, -135, 405, ...

Answer 1

Great, so we need to look at common ratios.
do you remember how to get the common ratio from a given geometric sequence?

Answer 2

I don't D: Please refresh my memory

Answer 3

press F5 ^.^

Answer 4

all you need to do is divide the 2nd term by the 1st term
that'll give it to you

Answer 5

in light of that information, what would the common ratio for A be?

Answer 6

A) r=

Answer 7

for choice A,
what is the 2nd term of the sequence?

Answer 8

Sorry!

Answer 9

20!

Answer 10

the first term is 5, and the 2nd is 20--- So 20 divided by 5 = 4.
We found our first common ratio
so r=4 for A

can you repeat that process for choice B?

Answer 11

3 for the second?

Answer 12

good!

Answer 13

do it again for choice C. We're looking for any two that end up having the same common ratio

Answer 14

3.5 for C, 4 for D, and -3 for E!

Answer 15

I am thinking B, and E then.

Answer 16

But E is negative D:

Answer 17

No. B is 3 and where E is -3

Answer 18

so A=4 and so does D=4, right?
Therefore A and D have the same ratio.

Answer 19

I forgot about A aha

Answer 20

Thanks so much:D :D

Answer 21

this is why you go over what you do, to avoid such silly mistakes.. and no problem!

Answer 22

You made it so much easier than what I was taught ;-;