Using the hypergeometric distribution, it is found that there is a 0.4286 = 42.86% probability of getting 2 of the same colour.
The marbles are chosen without replacement, hence the <em>hypergeometric </em>distribution is used to solve this question.
<h3>What is the hypergeometric distribution formula?</h3>
The formula is:


The parameters are:
- x is the number of successes.
- N is the size of the population.
- n is the size of the sample.
- k is the total number of desired outcomes.
In this problem:
- There is a total of 3 + 4 = 7 marbles, hence N = 7.
- Of those, 3 are blue, hence k = 3.
- 2 marbles will be taken, hence n = 2.
The probability of getting 2 of the same colour is the sum of P(X = 0), which is both red, with P(X = 2), which is both blue, then:



Hence:

0.4286 = 42.86% probability of getting 2 of the same colour.
You can learn more about the hypergeometric distribution at brainly.com/question/4818951
Four times a number would equal 4n
Answer:
Step-by-step explanation:
Average rate of change is just using the slope formula: (y2-y1)/(x2-x1).
Answer:
a. or 
Step-by-step explanation:
Slope is equal to y1-y2 over x1-x2.
So the equation would be:

2-(-1)=2+1=3
-3-(-1)=-3+1=-2
So the answer is:

15% = 0.15
tip = 15 * 0.15 = 2.25
5% = 0.05
tax = 15 * 0.15 = 0.75
total = 15 + 0.75 + 2.25 = $18