Alex draws the scale model shown as a plan for a large wall mosaic. 10 cm 12 cm

A sample of 900 college freshmen were randomly selected for a national survey. Among the survey participants, 372 students were

Rufina [12.5K]

Answer:

a) $ME=2.58 \sqrt{\frac{0.413(1-0.413)}{900}}=0.0423$

b) $0.413 - 2.58 \sqrt{\frac{0.413(1-0.413)}{900}}=0.371$

Step-by-step explanation:

1) Data given and notation

n=900 represent the random sample taken

X=372 represent the students were pursuing liberal arts degrees

$\hat p=\frac{372}{900}=0.413$ estimated proportion of students were pursuing liberal arts degrees

$\alpha=0.01$ represent the significance level

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

p= population proportion of students were pursuing liberal arts degrees

2) Solution to the problem

The confidence interval would be given by this formula

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

For the 99% confidence interval the value of $\alpha=1-0.99=0.01$ and $\alpha/2=0.005$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=2.58$

The margin of error is given by:

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

If we replace we have:

$ME=2.58 \sqrt{\frac{0.413(1-0.413)}{900}}=0.0423$

And replacing into the confidence interval formula we got:

$0.413 - 2.58 \sqrt{\frac{0.413(1-0.413)}{900}}=0.371$

$0.413 + 2.58 \sqrt{\frac{0.413(1-0.413)}{900}}=0.455$

And the 99% confidence interval would be given (0.371;0.455).

We are confident (99%) that about 37.1% to 45.5% of students were pursuing liberal arts degrees.

7 0

2 years ago

Timothy makes reduced copies of a photograph that has an actual length of 8 in. Each time he presses the reduce button on the co

Aleksandr-060686 [28]

Answer:

length of the photograph will be 4.2 in. after pressing the button 5 times.

Step-by-step explanation:

By pressing the button, every time size of the photograph gets reduced by 12%.

Therefore, the sequence formed by the reduced sizes of the photo will be a geometric sequence and the formula for the size of the reduced image will be,

L = $l(1-\frac{12}{100})^{n}$

Where l = Actual length of the photograph

L = length of the reduced image

n = Number of times the button has been pressed

For l = 8 in. and n = 5

L = $8(1-0.12)^{5}$

= $8(0.88)^{5}$

= 4.22 in

L ≈ 4.2 in.

Therefore, length of the photograph will be 4.2 in. after pressing the button 5 times.

3 0

2 years ago

Kyle asks his friend Jane to guess his age and his grandmother’s age. Kyle says his grandmother is not more than 80 years old. H

melamori03 [73]

#1 is incorrect. The first equation says that his grandmother is not more than 80 years old. If you confine yourself to whole numbers, then she could be 80 but not more. That inequality should be written as g < 81 or if you are a purist, g≤ 80.

The second equation is correct. At the very most her age is equal to 3k - 3 so at most it would be written as g = 3k - 3.

Since it is not that much, you would write it as g ≤ 3k - 3

6 0

2 years ago

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John is selling his pizza for $6 per slice in an area of high demand. However, customers are not buying his pizza.

elena-14-01-66 [18.8K]

For starters lower the price

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2 years ago

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The midpoint of a line can be found using either a compass and straightedge construction or a straightedge and tracing paper con

Klio2033 [76]

The midpoint of a line can be found using either a compass and straightedge <span>construction or a straightedge and tracing paper construction.
</span>true :)

4 0

2 years ago

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