## ramirokool 3 years ago Which of the following is the formula for the geometric sequence? 3, 15, 75, 375 ... Answer an=3(5)n-1 an=5(3)n-1 an=12(3)n-1 an=5(12)n-1

1. ramirokool

2. campbell_st

well the 1st term is 3 and the common ratio is 5 so \[T_{n} = ar^{n -1}\] is the formula for a term in a geometric series... substitute a = 3 and r = 5 into the formula to find the formula.

3. ramirokool

It would be A than (:

4. campbell_st

well you have all the information just substitute and trust your algebra skills.

5. ramirokool

@Shadowys is it A or B

6. ramirokool

I go with B campbell sir.

7. ramirokool

I did it on my sheet.

8. ramirokool

9. ramirokool

@nubeer can you confirm if it B

10. ramirokool

@jiteshmeghwal9 Is it B?

11. nubeer

its not B option

12. jiteshmeghwal9

Sorry..... No idea but go with the tips given by @CarlosGP

13. ramirokool

So I'ma go with A or C

14. ramirokool

@nubeer Mis calculation it D

15. nubeer

still wrong.. maybe read again the guidelines told by Campbell...

16. campbell_st

wow @ramirokool, you don't have a lot of confidence in your skills.

17. ramirokool

@campbell_st I know the answer A but no one won't confirm it..@nubeer Show step by step please.

18. ramirokool

@nubeer show me step by step I know it A

19. ramirokool

@jiteshmeghwal9 I GOT IT A

20. ramirokool

YESSSSSSSSSSSS LORD

21. nubeer

ya its A

22. nubeer

and it dont have any steps.. most step you need is done just find r and subsitute it.