Answer:
-6x-4
Step-by-step explanation:
Using the binomial distribution, it is found that:
The probability that the student will get 15 correct questions in this test by guessing is 0.0207 = 2.07%.
For each question, there are only two possible outcomes, either the guess is correct, or it is not. The guess on a question is independent of any other question, hence, the binomial distribution is used to solve this question.
Binomial probability distribution
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:
- There are 20 questions, hence
.
- Each question has 2 options, one of which is correct, hence

The probability is:

In which:







Then:

The probability that the student will get 15 correct questions in this test by guessing is 0.0207 = 2.07%.
You can learn more about the binomial distribution at brainly.com/question/24863377
Answer:
5 minutes
Step-by-step explanation:
To get the response to this question, it would be required to convert both times to seconds alone.
For the first, the time It takes to flash is 1 minute 15 seconds which is same as 75 seconds
For the second, it takes 1 minute 40 seconds which is same as 100 seconds.
Now to get the time they would flash together, we need to know their lowest common multiples. The values involved are 75 and 100. Thus, the lowest common multiple of both is 300.
This is equivalent to 300 seconds which is 5 minutes time
In the right angled triangle ACD shown with isosceles triangle ABC and ADC, AB = AC = AD
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
A triangle is a polygon that has three sides and three angles. Types of triangles are<em> isosceles, equilateral and scalene</em>.
In the diagram shown:
AB = AC = AD
In the right angled triangle ACD shown with isosceles triangle ABC and ADC, AB = AC = AD
Find out more on equation at: brainly.com/question/2972832
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