9514 1404 393
Answer:
(a) 2/100
Step-by-step explanation:
To determine the value of a digit, set all other digits to zero. Your digit has a value of ...
0.020 . . . two hundredths = 2/100
If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.
(1/2)^(number of half-lives) = 3%
number of half-lives = ln(0.03) / ln(0.5)
This gives the number of half-lives as 5.06.
Then 300 days = (5.06)(length of 1 half-life)
length of 1 half-life = 300 / 5.06 = 59.29 days
Using the binomial distribution, it is found that the probability that at least 12 of the 13 adults require eyesight correction is of 0.163 = 16.3%. Since this probability is greater than 5%, it is found that 12 is not a significantly high number of adults requiring eyesight correction.
For each person, there are only two possible outcomes, either they need correction for their eyesight, or they do not. The probability of a person needing correction is independent of any other person, hence, the binomial distribution is used to solve this question.
<h3>What is the binomial 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:
- A survey showed that 77% of us need correction, hence p = 0.77.
- 13 adults are randomly selected, hence n = 13.
The probability that at least 12 of them need correction for their eyesight is given by:

In which:



Then:

The probability that at least 12 of the 13 adults require eyesight correction is of 0.163 = 16.3%. Since this probability is greater than 5%, it is found that 12 is not a significantly high number of adults requiring eyesight correction.
More can be learned about the binomial distribution at brainly.com/question/24863377
we have

The solution is the shaded area above the dotted line
we know that
If a point is a solution of the inequality, then the coordinates of the point must satisfy the inequality
We will verify all cases to determine the solution of the problem
<u>Case A)</u> Point 

Substitute the value of x and y in the inequality and verify

-------> is not true
therefore
the point
is not a solution of the inequality
<u>Case B)</u> Point 

Substitute the value of x and y in the inequality and verify

-------> is true
therefore
the point
is a solution of the inequality
<u>Case C)</u> Point 

Substitute the value of x and y in the inequality and verify

-------> is not true
therefore
the point
is not a solution of the inequality
<u>Case D)</u> Point 

Substitute the value of x and y in the inequality and verify

-------> is not true
therefore
the point
is not a solution of the inequality
therefore
<u>the answer is the Point B</u>

To better understand the problem see the attached figure
Doesn't ask what kind of cd's and what age it was aimed at