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
Answer:
P(X > 25) = 0.69
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
The sale prices for a particular car are normally distributed with a mean and standard deviation of 26 thousand dollars and 2 thousand dollars, respectively.
This means that 
Find P(X>25)
This is 1 subtracted by the pvalue of Z when X = 25. So



has a pvalue of 0.31
1 - 0.31 = 0.69.
So
P(X > 25) = 0.69