Im trying to do IXL and I dont understand the way my teacher teaches (ironic right?)

A study of the career paths of hotel general managers sent questionnaires to an SRS of 280 hotels belonging to major U.S. hotel

const2013 [10]

Answer and Step-by-step explanation:

we have the following data:

Point estimate = sample mean = \ bar x = 12.39

Population standard deviation = \ sigma = 3.7

Sample size = n = 177

a) the margin of error with a 90% confidence interval

α = 1 - 90%

alpha = 1 - 0.90 = 0.10

alpha / 2 = 0.05

Z \ alpha / 2 = Z0.05 = 1,645

Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)

we replace:

E = 1.645 * (3.7 / \ sqrt177)

Outcome:

E = 0.46

b) margin of error with a 99% confidence interval

α = 1-99%

alpha = 1 - 0.99 = 0.01

alpha / 2 = 0.005

Z \ alpha / 2 = Z0.005 = 2,576

Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)

we replace:

E = 2,576 * (3.7 / \ sqrt177)

Outcome:

E = 0.72

c) A larger confidence interval value will increase the margin of error.

6 0

2 years ago

A recent survey by the American Cancer Society shows that the probability that someone is a smoker is P(S) = 0.19. It has also d

nekit [7.7K]

0.19*0.158=0.03002 -------> 0.03

8 0

2 years ago

Which statements about the system are true?

Kruka [31]

2 Answers:

B) The lines are parallel
C) The lines have the same slope.

Parallel lines always have equal slope, but different y intercepts.

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Explanation:

Let's solve the second equation for y

3y - x = -7

3y = -7+x

3y = x-7

y = (x-7)/3

y = x/3 - 7/3

y = (1/3)x - 7/3

The equation is in y = mx+b form with m = 1/3 as the slope and b = -7/3 as the y intercept. We see that the first equation, where y was already isolated, also has a slope of m = 1/3. The two equations of this system have the same slope. Choice C is one of the answers.

However, they don't have the same y intercept. The first equation has y intercept b = -4, while the second has b = -7/3. This means that they do not represent the same line. They need to have identical slopes, and identical y intercepts (though the slope can be different from the y intercept of course) in order to have identical lines. So we can rule out choice D and E because of this.

Because the two equations have the same slope, but different y intercepts, this means the lines are parallel. Choice B is the other answer.

Parallel lines never touch or intersect, which in turn means there is no solution point. A solution point is where the lines cross. We can rule out choice A.

I recommend using your graphing calculator, Desmos, GeoGebra, or any graphing tool (on your computer or online) to graph each equation given. You should see two parallel lines forming. I used GeoGebra to make the graph shown below.