Answer:
0.3891 = 38.91% probability that only one is a second
Step-by-step explanation:
For each globet, there are only two possible outcoes. Either they have cosmetic flaws, or they do not. The probability of a goblet having a cosmetic flaw is independent of other globets. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
17% of its goblets have cosmetic flaws and must be classified as "seconds."
This means that
Among seven randomly selected goblets, how likely is it that only one is a second
This is P(X = 1) when n = 7. So
0.3891 = 38.91% probability that only one is a second