6.According to one study, 61% of the population swallow at least one spider per year in their sleep. Based on this study, what is the probability that exactly 7 of 10 randomly selected people have swallowed at least one spider in their sleep in the last year.

70%
22%
1%
34%

Question

6.According to one study, 61% of the population swallow at least one spider per year in their sleep. Based on this study, what is the probability that exactly 7 of 10 randomly selected people have swallowed at least one spider in their sleep in the last year.

70%
22%
1%
34%

anonymous · Answer

hahahaha xD

rc94 · Answer

I believe this is binomial distribution, so that you have X is distributed as a binomial with probability 0.61, and '10' events.

So for exactly 7 we have (10 choose 7) * 0.61^7 * 0.39^3 = (about) 22%