Answer:
1. 3.5 units up
2. 3/4 units down.
3. down 3 units
4. up 2 units, right 1
5. up 4 units, right 3
6. down 4 units, left 2
Step-by-step explanation:
Answer:
C) 21 girls : 9 boys
Step-by-step explanation:
You just have to compare the ratio you're given to the answers and see if the ratios from the answers match up to the ratio you were given. The reason C is the answer is because if you divide by 3 in the ration, it is the same as the ratio you were given, 7:3
Using the binomial distribution, it is found that there is a:
a) 0.9298 = 92.98% probability that at least 8 of them passed.
b) 0.0001 = 0.01% probability that fewer than 5 passed.
For each student, there are only two possible outcomes, either they passed, or they did not pass. The probability of a student passing is independent of any other student, hence, the binomial distribution is used to solve this question.
<h3>What is the binomial probability distribution formula?</h3>
The formula is:


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:
- 90% of the students passed, hence
.
- The professor randomly selected 10 exams, hence
.
Item a:
The probability is:

In which:




Then:

0.9298 = 92.98% probability that at least 8 of them passed.
Item b:
The probability is:

Using the binomial formula, as in item a, to find each probability, then adding them, it is found that:

Hence:
0.0001 = 0.01% probability that fewer than 5 passed.
You can learn more about the the binomial distribution at brainly.com/question/24863377