Answer:
11/20
Step-by-step explanation:
At the beginning, the number of marbles in the box are:
10 green marbles
11 white marbles
The first marble chosen is green, and then it is not replaced in the box. Therefore, the number of green marbles left in the box is 9.
Therefore, the total number of marbles left in the box is:
Now we want to find the probability to choose a white marble. The number of white marble is
Therefore, the probability of choosing a white marble is:
Answer:
0.3874 = 38.74% probability that exactly 9 of the 10 consumers recognize her brand name.
0.6126 = 61.26% probability that the number who recognize her brand name is not nine.
Step-by-step explanation:
For each consumer, there are only two possible outcomes. Either they recognize the name, or they do not. The probability of a customer recognizing the name is independent of anu other customer. This means that the binomial probability distribution is used 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.
The brand name of Mrs. Fields (cookies) has a 90% recognition rate.
This means that .
Sample of 10
This means that
Find the probability that exactly 9 of the 10 consumers recognize her brand name.
This is P(X = 9). So
0.3874 = 38.74% probability that exactly 9 of the 10 consumers recognize her brand name.
Also, find the probability that the number who recognize her brand name is not nine.
1(100%) subtracted by those who recognize. So
1 - 0.3874 = 0.6126
0.6126 = 61.26% probability that the number who recognize her brand name is not nine.