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.

Question

(1 point)
Responses

70%
70%

22%
22%

1%
1%

34%

Answer 1

1%

To calculate this probability, we can use the binomial probability formula:

P(x) = (n choose x) * p^x * (1-p)^(n-x),

where n = 10 (number of trials), x = 7 (number of successes), p = 0.61 (probability of success).

Plugging in these values, we get:

P(7) = (10 choose 7) * (0.61)^7 * (1-0.61)^(10-7)
P(7) = 120 * (0.61)^7 * (0.39)^3
P(7) ≈ 0.009

Converting this to a percentage, we get approximately 0.9%, which is closest to 1%.