Sahil Khan

A small college has 800 students, 10 percent of which are left-handed. Suppose we randomly select 8 students, because SRS = 8, and assume L = 3.

Also, assume we have to find the probability that exactly 3 out of the 8 students are left-handed, or the probability that L=3.

We use the binomial distribution for calculating this

^{n}C_{r} \cdot p^{r} (1-p)^{n-r}

p is the probability of successes which is 10% or 0.1, n = 8, r = 3. Plugging these in we get


= 56 (0.001)(0.9)^{5}


So, the probability of getting 3 lefthanded students is 0.033.

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Binomial probability example (video) | Khan Academy

We can use the binomial distribution to find the probability of getting a certain ... Binomial random variables ... Binomial mean and standard deviation formulas ... It may not be exact because this is experimental data, but it should be close. ... AP® is a registered trademark of the College Board, which has not reviewed this  ...

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