Question

When treated with an anabiotic, 97% of all the dolphins are cured of an ear infection. if 6 dolphins are treated find the probability that exactly 3 are cured.

The probability is _____
(Round your answer to 4 decimal places.)

Answer 1

0.0005

Explanation:

this is a binomial experiment -- they are either cured or not, and the outcome is random

probability = n choose r * p^r * q^(n-r)

here, n = number of trials, r = number of successes desired, p = probability event occurs, and q = probability event doesn't occur

probability = n choose r * p^r * q^(n-r) = 6 choose 3 * 0.97^3 * 0.03^(6-3)

= 0.00049284342 rounding to 0.0005