CAN YOU HELP ME PLEASE!!

in a class of 40 students, 24 are over the age of 21 and 16 are 21 or younger. Biff is over the age of 21. A student is selected

LenKa [72]

Answer:

3. 60% probability the student is over the age of 21.4

4. 4.17% probability Biff was selected if you know the student selected was over the age of 21.

5. 0% probability Biff was selected if you know the student selected was 21 or younger

Step-by-step explanation:

A probability is the number of desired outcomes divided by the number of total outcoes.

In this question:

40 students

24 over the age of 21.

16 are 21 or younger.

3. Find the probability the student is over the age of 21.

24 of the 40 students are over the age of 21.

24/40 = 0.6

60% probability the student is over the age of 21.4

4. Find the probability Biff was selected if you know the student selected was over the age of 21.

24 students over the age of 21, one of which is Biff.

1/24 = 0.0417

4.17% probability Biff was selected if you know the student selected was over the age of 21.

5. Find the probability Biff was selected if you know the student selected was 21 or younger

Biff is not 21 or younger, he is over 21, so there are no desired outcomes.

So, 0% probability Biff was selected if you know the student selected was 21 or younger

8 0

3 years ago

Which equation does the graph represent (see picture)

egoroff_w [7]

Y=Mx +b

B is 0 because that’s where the graph intercepts the y axis.

M is found by picking any two points and finding the rise and run because m is equal rise/run

Points of choice: (-2,4) and (2,-4)

=2−1/2−1 = -8/4

m is equal -2

Y= -2X

Look at the picture below to differentiate between positive and negative slopes.

8 0

3 years ago

PLZZZZZZZ HELPP Which ordered pair is the solution to the system of equations? {y=2x−15} {4x+3y=−5} (5, −5) (4, −7) (0, 6) (7

Sophie [7]

solution is (4, - 7 )

given the equations

y = 2x - 15 → (1)

4x + 3y = - 5 → (2)

substitute y = 2x - 15 into (2)

4x + 3(2x - 15) = - 5

4x + 6x - 45 = - 5

10x - 45 = - 5 ( add 45 to both sides )

10x = 40 ( divide both sides by 10 )

x = 4

substitute x = 4 into (1) for corresponding value of y

y = (2 × 4 ) - 15 = 8 - 15 = - 7

solution is (4, - 7 )

8 0

3 years ago

In preparation for an earnings report, a large retailer wants to estimate p= the proportion of annual sales

mr Goodwill [35]

Using the z-distribution, it is found that the 95% confidence interval for the proportion of sales that occured in December is (0.1648, 0.2948).

<h3>What is a confidence interval of proportions?</h3>

A confidence interval of proportions is given by:

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which:

$\pi$ is the sample proportion.

z is the critical value.

n is the sample size.

In this problem, we have a 95% confidence level, hence $\alpha = 0.95$ , z is the value of Z that has a p-value of $\frac{1+0.95}{2} = 0.975$ , so the critical value is z = 1.96.

The sample size and the estimate are given by:

$n = 161, \pi = \frac{37}{161} = 0.2298$

Hence:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2298 - 1.96\sqrt{\frac{0.2298(0.7702)}{161}} = 0.1648$

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2298 + 1.96\sqrt{\frac{0.2298(0.7702)}{161}} = 0.2948$

The 95% confidence interval for the proportion of sales that occured in December is (0.1648, 0.2948).

More can be learned about the z-distribution at brainly.com/question/25890103

5 0

2 years ago

What option is correct: A or B

Yuliya22 [10]

The image isn’t visible. Would recommend reposting

5 0

3 years ago