Suppose you have a coin with 4 fair sides, flip it 5 times, and want to know the probability of 5 heads. This is(adsbygoogle = window.adsbygoogle || []).push({});

K(10,5) * (0.25)^{5}* (1-0.25)^{5}= K(10,5)*0.25^{5}*0.75^{5}

Or more generally for any binomially distributed outcome:

1) p(x=r) = p^{r}*(1-p)^{n-r}*K(n,r)

But also we must have that:

2) p(x=r) = K(n,r)/total combinations = K(n,r)/4^{n}

How do you show that 1) and 2) are equivalent?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Binomial distribution

**Physics Forums | Science Articles, Homework Help, Discussion**