Question

A bacteria culture begins with 15 bacteria which double in amount every hour. How many bacteria exist in the culture at the 13th hour?

61,440

782,580

7,971,615

23,914,845

Answer 1

@iambatman @texaschic101 @goformit100

Answer 2

15 -- 1st hr
15 x 2 = 30 -- 2nd hr
30 x 2 = 60 -- 3rd hr
60 x 2 = 120 -- 4th hr
120 x 2 = 240 -- 5th hr
240 x 2 = 480 -- 6th hr
480 x 2 = 960 -- 7th hr
960 x 2 = 1920 -- 8th hr
1920 x 2 = 3840 -- 9th hr
3840 x 2 = 7680 -- 10th hr
7680 x 2 = 15360 -- 11th hr
15360 x 2 = 30720 -- 12th hr
30720 x 2 = 61440 -- 13th hr

I know there is probably an easier way to do this....I just don't know it

Answer 3

I know! I tried doing it this way but for some reason I didn't get an available answer or I read it wrong or something idk something just felt off about it. But thanks!

Answer 4

you could probably set it up as a geometric sequence to solve it

Answer 5

That's what they wanted, if I could bounce like 1-2 more off of you I'd appreciate it!

Answer 6

I can try

Answer 7

Actually I coulda just done this *facepalm*

Answer 8

I am going with answer choice 3 because the common ratio is -2

Answer 9

were you supposed to show your work on the first problem ?

Answer 10

Ok thanks so much, last one is this one, and no.

Answer 11

sorry..I do not know this one :(

Answer 12

Is there someone here that you could possible tag or let me tag that you know knows this?

Answer 13

@hartnn ...can you help with this