Plzzzzz help! Will mark brainliest

Question 17

Rufina [12.5K]

Answer:

698 fishes

Step-by-step explanation:

Generally, we can represent an exponential growth function as;

y = a•(1 + r)^t

originally, there were 3 fishes

The original value in this case means a = 3

After 6 weeks, there were 31

31 in this case is y

r is the increase percentage or rate

t is the time

So, we have it that;

31 = 3•(1 + r)^6

31/3 = (1 + r)^6

10.33 = (1 + r)^6

ln 10.33 = 6 ln (1 + r)

ln 10.33/6 = ln (1 + r)

e^0.3892 = (1 + r)

1 + r = 1.476

r = 1.476-1

r = 0.476 or 47.6%

So the growth percentage or rate is 47.6%

For 14 weeks, we simply have the value of t as 14;

So ;

y = 3•(1 + 0.476)^14

y = 3(1.476)^14

y = 698 fishes

8 0

3 years ago

Several years ago, 50% of parents who had children in grades K-12 were satisfied with the quality of education the students r

galina1969 [7]

Answer:

The 95% confidence interval for the proportion of parents that are satisfied with their children's education is (0.4118, 0.4618). 0.5 is not part of the confidence interval, so this represents evidence that parents' attitudes toward the quality of education have changed.

Step-by-step explanation:

We have to see if 50% = 0.5 is part of the confidence interval.

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

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

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 1095, \pi = \frac{478}{1095} = 0.4365$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4365 - 1.96\sqrt{\frac{0.4365*0.5635}{1095}} = 0.4118$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4365 + 1.96\sqrt{\frac{0.4365*0.5635}{1095}} = 0.4612$

The 95% confidence interval for the proportion of parents that are satisfied with their children's education is (0.4118, 0.4618). 0.5 is not part of the confidence interval, so this represents evidence that parents' attitudes toward the quality of education have changed.

5 0

3 years ago

Solve the equation. 6 = 2(x + 8) - 5x A. 2/3 B. 3 1/3 C. - 2/3 D. -3 1/3

Zinaida [17]

6 = 2(x+8) - 5x
⇒ 2x+ 2*8 -5x= 6
⇒ (2x -5x)+ 16= 6
⇒ -3x = 6 -16
⇒ -3x = -10
⇒ x= -10/(-3)
⇒ x= 10/3
⇒ x= 3 1/3

The correct answer is B. 3 1/3~

4 0

3 years ago

Read 2 more answers

7(4x) simplifying expressions pls help with this!

Slav-nsk [51]

7(4x) = 28x

Hope this helps :)