What is a correct first step in solving the inequality –4(3

National data in the 1960's showed that about 44% of the adult population had never smoked cigarettes. In 1995 a national health

Marta_Voda [28]

Answer:

a) $0.52 - 1.96\sqrt{\frac{0.52(1-0.52)}{881}}=0.487$

$0.52 + 1.96\sqrt{\frac{0.52(1-0.52)}{881}}=0.553$

The 95% confidence interval would be given by (0.487;0.553)

b) After see the confidence interval we see that the lower limits 0.487>0.44 with 0.44 or 44% the estimated proportion for 1960, we can conclude that we have a significant increase in the adult proportion had never smoked cigarettes.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

Part a

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The confidence interval for the mean is given by the following formula:

$\hat p \pm z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$

If we replace the values obtained we got:

$0.52 - 1.96\sqrt{\frac{0.52(1-0.52)}{881}}=0.487$

$0.52 + 1.96\sqrt{\frac{0.52(1-0.52)}{881}}=0.553$

The 95% confidence interval would be given by (0.487;0.553)

Part b

After see the confidence interval we see that the lower limits 0.487>0.44 with 0.44 or 44% the estimated proportion for 1960, we can conclude that we have a significant increase in the adult proportion had never smoked cigarettes at 5% of significance.

4 0

4 years ago

Please help!!!!!!!!MAX POINTS

Komok [63]

Answer:

3, 5, 7, 9

Step-by-step explanation:

f(x) = 2x + 5

x = -1: f(-1) = 3

x = 0: f(0) = 5

x = 1: f(1) = 7

x = 2: f(2) = 9

3 0

3 years ago

Read 2 more answers

Ryan practiced 43.2 minutes on Monday on his violin. Tuesday, he practiced 37.48 minutes. If he practiced a total of 114.34 minu

Nesterboy [21]

Answer:

Ryan practiced 33.66 minutes on Wednesday

Step-by-step explanation:

You do 43.2+37.48 and it equals 80.68

Then you do 114.34-80.68 which equals 33.66

6 0

3 years ago

Can someone please help me?

Eddi Din [679]

To solve these types of problems, we need to break it down and see what each part represents.

(11) 3m
(12) j-10
(13) d+4
(14) 4p

All we must do is understand some basic keywords, such as times which represents multiplication, less which represents subtraction, and more which can represent addition or multiplication.<span />

5 0

4 years ago

Tori is studying Japan and decides to paint a Japanese flag. She first paints a white rectangle that is 36 inches long and 24 in

Salsk061 [2.6K]

First compute the area of the rectangle:
$24\times36=864inches^2$
We have to find the radius of the circle:
circonférence of circle given radius is: $C=2\pi r$
We get the equation: $2\pi r=43.96$
Solving the above equation for r we get: $r=7$
Compute the area of the circle like this: $\pi r^3=\pi7^2=154inches^2$
The white area is the difference of the area of the rectangle and the area of the circle:
$864-154=710inches^2$

5 0

3 years ago

What is a correct first step in solving the inequality –4(3 – 5x)≥ –6x + 9?