**Question description:**

*This user has given permission to use the problem statement for this blog.*

Help!
In a coin toss I have a 1 in 2 (fifty-fifty) chance of getting heads or tails. I need a formula to determine my chance of getting 4 heads in a row or 4 tails in a row out of 10 coin tosses. If I get 4 in a row I win. What formula can I use to determine my chances of winning if I repeat the 10 tosses for hundreds or thousands of times? I get as far as =RANDBETWEEN(0,1) but I have not been able to figure out what formula to use to determine if there are 4 in a row in a group of 10 tosses, times thousands of groups with 10 tosses in each group. Thank-you for any help you can provide.

Solved by V. F. in 51 mins

This is the chat thread from the real Excelchat help session. It contains no private user information.

User
18/03/2018 - 07:07

p.s., how can i save a copy of our chat and worksheet so I can study/understand it after our session ends?

Excelchat Expert
18/03/2018 - 07:07

Hi Welcome to Gotit

Excelchat Expert
18/03/2018 - 07:08

Its a probability question

Excelchat Expert
18/03/2018 - 07:09

10C2/2^10

Excelchat Expert
18/03/2018 - 07:09

is the propability

Excelchat Expert
18/03/2018 - 07:09

10C4

Excelchat Expert
18/03/2018 - 07:09

/2^10

User
18/03/2018 - 07:11

ok, I understand that it is probability,

Excelchat Expert
18/03/2018 - 07:12

use 10C4/2^10

Excelchat Expert
18/03/2018 - 07:13

(10*9*8*7/4*3*2*1)/2^10

User
18/03/2018 - 07:17

Probability of 4 heads or four tailess in a row with 10 tosses, repeated multiple times, each group of 10 distinct from the next group of 10.

Excelchat Expert
18/03/2018 - 07:19

hello

Excelchat Expert
18/03/2018 - 07:19

its a probability question

Excelchat Expert
18/03/2018 - 07:19

not excel related

User
18/03/2018 - 07:20

hello, i'm still here. but how can i formulate it in excel?

Excelchat Expert
18/03/2018 - 07:21

you can't find it but you can simulate

User
18/03/2018 - 07:22

that is my question, what formula can i use to simulate it in excel

Excelchat Expert
18/03/2018 - 07:26

four heads in a row we can find using excel

Excelchat Expert
18/03/2018 - 07:27

we can find n heads tossed in 10 tosses

User
18/03/2018 - 07:28

yes, using =RANDBETWEEN(0,1)

User
18/03/2018 - 07:30

Here is the actual wording of the problem I'm trying to figure out how to simulate.

User
18/03/2018 - 07:30

You are going to play a game where you bet a dollar and get to flip a coin ten (10) times. If you get four (4) heads in a row, you win. If you make the tenth flip without getting four heads in a row, you lose.
Run this game ten thousand times (10,000).
Approximately what is the probability that you will win?

Excelchat Expert
18/03/2018 - 07:34

I made the formula

User
18/03/2018 - 07:35

pardon me? I don't see it.

Excelchat Expert
18/03/2018 - 07:36

I made for 10 tosses

Excelchat Expert
18/03/2018 - 07:36

D3,D4

Excelchat Expert
18/03/2018 - 07:36

E3,E4,F4,F5

User
18/03/2018 - 07:38

thank you. that was not showing on my screen, I had to scroll over to see it, How can I save this so i have time to study and copy it b4 we time out?

Excelchat Expert
18/03/2018 - 07:38

yes

User
18/03/2018 - 07:39

how?

Excelchat Expert
18/03/2018 - 07:39

DOWNLOAD THE SHEET

Excelchat Expert
18/03/2018 - 07:40

Please end the session

User
18/03/2018 - 07:41

i do not see where on my screen to download it

Excelchat Expert
18/03/2018 - 07:41

Where s the preview sheet?

Excelchat Expert
18/03/2018 - 07:42

have you done anything?

Excelchat Expert
18/03/2018 - 07:42

I can't see sheet in document preview window

Excelchat Expert
18/03/2018 - 07:44

Hello

User
18/03/2018 - 07:45

i have the Document Preview sheet on the screen, but i do not see any command to download it.

Excelchat Expert
18/03/2018 - 07:45

I am unable to preview document window

Excelchat Expert
18/03/2018 - 07:46

I think I have to write formula again

User
18/03/2018 - 07:48

I can see the preview sheet, and when I click on the cells I see the formula, but I am unable to find anything that allows me to download it

Excelchat Expert
18/03/2018 - 07:49

Copy the data to your sheet CTRL C and CTRL V

User
18/03/2018 - 07:51

ok, thank you, but that is copy and paste, not download.

Excelchat Expert
18/03/2018 - 07:52

I will send you the sheet

Excelchat Expert
18/03/2018 - 07:52

it

Excelchat Expert
18/03/2018 - 07:52

wait

User
18/03/2018 - 07:53

thankyou, my e-mail is iadtjff@yahoo.com

Excelchat Expert
18/03/2018 - 07:55

oK

Excelchat Expert
18/03/2018 - 07:55

Please end the session

User
18/03/2018 - 07:55

ok. goodbye

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