Question

@robtobey A geometric sequence is obtained by placing five terms between 10 and 640. What is the common ratio equal to ?

Answer 1

If r is the common ratio, then what is the next term right after 10?

Answer 2

nothing the question was just like this

Answer 3

do you agree that it would be 10*r or 10r ?

Answer 4

since to get the next term, you multiply the last term by r

hopefully that makes sense

Answer 5

nope mate the answer will be 4 2 3 5 or 6

Answer 6

don't worry about the answer choices right now

Answer 7

ok

Answer 8

11

Answer 9

idk what you mean

the term that comes after 10 is 10r

the term after 10r is 10r*r = 10r^2

etc etc until you get to 640

Answer 10

you should get this sequence:

10, 10r, 10r^2, 10r^3, 10r^4, 10r^5, 640

Answer 11

ok

Answer 12

the next term after 10r^5 is 10r^6

therefore,

10r^6 = 640

Answer 13

solve 10r^6 = 640 for r to get your answer

Answer 14

which is 4

Answer 15

I agree, to see an example look at

1,2,4,8,16,32,64

64/1=2^6

Answer 16

r = 4 is false

Answer 17

sorry it will be 2

Answer 18

r = 2 is true

Answer 19

thanks man can I ask 1 more question

Answer 20

sure

Answer 21

thank you then now I am writing

Answer 22

Did you get the question because my drawing is not good enough ?

Answer 23

what is the area of the circle given

Answer 24

hint: use A = pi*r^2

Answer 25

it has given no area

Answer 26

use that formula I gave to compute the area

Answer 27

r = 5 in this case

Answer 28

ok but how

Answer 29

A = pi*r^2
A = pi*5^2
A = ???

Answer 30

25pi then wat will happen

Answer 31

now we will have another circle with the same center at point A

this new circle will have radius 3