Math Is Fun Forum

lindah

Member

Registered: 2010-01-25

Posts: 121

Tossing coins

http://imageshack.us/photo/my-images/685/52395533.png/

Hi guys,

Please ignore the second bit about the normdist.

May I confirm if my workings are correct?

1) State which distro it is from - Geometric

2) P(more than five tosses required) = 1  - (P[X=1] + P[X=2] + p[X=3] + P[X=4] + P[X=5])

X= getting TT
p= 0.5 x 0.5 = 0.25

I get
= 1 - (0.25 + 0.1875 + 0.141 + 0.1054 + 0.079)
= 0.2371

Last edited by lindah (2011-06-07 22:16:37)

gAr

Member

Registered: 2011-01-09

Posts: 3,482

Re: Tossing coins

Hi lindah,

1) is correct

2) is correct, accurate answer would be 0.2373046875

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"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

lindah

Member

Registered: 2010-01-25

Posts: 121

Re: Tossing coins

Thank you very much!!!

gAr

Member

Registered: 2011-01-09

Posts: 3,482

Re: Tossing coins

You're welcome!

---

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."