You are correct so yes the answer would be <span>-21<-8.
Hope this helped!</span>
Using the binomial distribution, it is found that there is a 0.7941 = 79.41% probability that at least one of them is named Joe.
For each student, there are only two possible outcomes, either they are named Joe, or they are not. The probability of a student being named Joe is independent of any other student, hence, the <em>binomial distribution</em> is used to solve this question.
<h3>Binomial probability distribution
</h3>
The parameters are:
- x is the number of successes.
- n is the number of trials.
- p is the probability of a success on a single trial.
In this problem:
- One in ten students are named Joe, hence
.
- There are 15 students in the class, hence
.
The probability that at least one of them is named Joe is:

In which:


Then:

0.7941 = 79.41% probability that at least one of them is named Joe.
To learn more about the binomial distribution, you can take a look at brainly.com/question/24863377
Using the definition of vertical angles you can set up the equation 3x+4=115, when solved you get x=37. Hope this helps!
If he wants to sell buttons, say
40 buttons, he will get a profit of 1000 cents. And one dollar is equal to 100
cents so he only earns 10 dollars. However, the costs for the machine are 125
dollars. Therefore he has a loss of 115 dollars.
Answer:

Step-by-step explanation:
Assuming this problem :"Only 30% of the students in a certain liberal arts college are males.
If two students from this college are selected at random, what is the probability that they are both males?"
Previous concepts
An independent event is an "event that has no connection to another event's chances of happening ". For this case we can assume that if one person is male and if we select another one the probability that this one would be male or female is totally indepedent from the first selection.
When we have two independent events let's say A and B and we want to find the probability that both events occurs at the same time we can use the following formula:

Solution to the problem
We can define some notation:
first person selected is a male
second person selected is male
On this case we want the probability that both would be males. And we can express this like this on math terms:

For this case we can assume that the two events are independent. And in order to find the probability for two events independents events we just need to multiply the probabilities of each one like this:
