Will give brainlest 5 star and thans

A researcher for an airline interviews all of the passengers on five randomly selected flights.

antoniya [11.8K]

Answer

Cluster sampling. See explanation below.

Step-by-step explanation:

For this case they not use random sampling since we are selecting people from flights. Because we select just 5 random flights.

Is not stratified sampling since we don't have strata clearly defined on this case, and other important thing is that in order to apply this method we need homogeneous strata groups and that's not satisfied on this case.

Is not convenience sampling because they NOT use a non probability method in order to select the people from the flights.

So then the only possible method is cluster sampling since we have clusters clearly defined (Passengers from the airlines), and we satisfy the condition of homogeneous characteristics on the clusters and an equal chance of being a part of the sample, since we are selecting RANDOMLY, the 5 flights to take the information.

6 0

3 years ago

What is the size of angle x !!!

klemol [59]

Answer:

∠x = 67°

Step-by-step explanation:

∠x = 67° because they both are inscribed angles of the same arc

7 0

3 years ago

Read 2 more answers

Find the equation of a line passing through points (-7, -10) , (-5, -20)

LuckyWell [14K]

You want to find the equation for a line that passes through the two points:

(-7,-10) and (-5,-20).

First of all, remember what the equation of a line is:

y = mx+b

here, m is the slope, b is the y-intercept

First, let's find what m is, the slope of the line...

The slope of a line is a measure of how fast the line "goes up" or "goes down". A large slope means the line goes up or down really fast (a very steep line). Small slopes means the line isn't very steep. A slope of zero means the line has no steepness at all; it is perfectly horizontal.

For lines like these, the slope is always defined as "the change in y over the change in x" or, in equation form:

So what we need now are the two points you gave that the line passes through.

Consider (-7,-10) as point #1, so the x and y numbers given will be called x1 and y1. Or, x1=-7 and y1=-10.

Consider (-5,-20), point #2, so the x and y numbers here will be called x2 and y2. Or, x2=-5 and y2=-20.

Now, just plug the numbers into the formula for m above, like this:

m= (-20 - -10)/(-5 - -7)

m= -10/2

m=-5

So, we have the first piece to finding the equation of this line, and we can fill it into y=mx+b like this:

y=-5x+b

Now, what about b, the y-intercept?

To find b, think about what your (x,y) points mean:

(-7,-10). When x of the line is -7, y of the line must be -10.

(-5,-20). When x of the line is -5, y of the line must be -20.

Because line passes through each one of these two points, right?

Now, look at our line's equation so far: y=-5x+b. b is what we want, the -5 is already set and x and y are just two "free variables" sitting there. We can plug anything we want in for x and y here, but we want the equation for the line that specifically passes through the two points (-7,-10) and (-5,-20).

So, why not plug in for x and y from one of our (x,y) points that we know the line passes through? This will allow us to solve for b for the particular line that passes through the two points you gave!.

You can use either (x,y) point you want.The answer will be the same:

(-7,-10). y=mx+b or -10=-5 × -7+b, or solving for b: b=-10-(-5)(-7). b=-45.

(-5,-20). y=mx+b or -20=-5 × -5+b, or solving for b: b=-20-(-5)(-5). b=-45.

See! In both cases we got the same value for b. And this completes our problem.

The equation of the line that passes through the points (-7,-10) and (-5,-20) is y=-5x-45.

8 0

3 years ago

Suppose that grade point averages of undergraduate students at one university have a bell-shaped distribution with a mean of 2.5

masya89 [10]

Answer:

$z= \frac{3.44-2.54}{0.45}=2$

$P(X>3.44) = P(Z>2) = 0.025$

Step-by-step explanation:

Previous concepts

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".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the grade points avergae of a population, and for this case we know the following properties

Where $\mu=2.54$ and $\sigma=0.45$

The empirical rule, also referred to as the three-sigma rule or 68-95-99.7 rule, is a statistical rule which states that for a normal distribution, almost all data falls within three standard deviations (denoted by σ) of the mean (denoted by µ). Broken down, the empirical rule shows that 68% falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ).

So we can find the z score for the value of X=3.44 in order to see how many deviations above or belowe we are from the mean like this:

$z= \frac{3.44-2.54}{0.45}=2$

So the value of 3.44 is 2 deviations above from the mean, so then we know that the percentage between two deviations from the mean is 95% and on each tail we need to have (100-95)/2 = 2.5% , because the distribution is symmetrical, so based on this we can conclude that:

$P(X>3.44) = P(Z>2) = 0.025$

5 0

3 years ago

Need helps asap. i will give brainliest

3241004551 [841]

The expression as a power is x¹⁰.

Given, the expression is xx⁴x⁴x

In exponents we have the power rule while multiplying.

the rule is that when bases are same, powers are added.

Exponent multiplication is the process of multiplying two terms with exponents. Depending on the base and the power, specific rules apply when multiplying exponents.

⇒ xx⁴x⁴x

base is same, power should be added.

⇒ x¹⁺⁴⁺⁴⁺¹

= x¹⁰

Hence the expression as a power is x¹⁰.

Learn more about Exponents here:

brainly.com/question/11975096

#SPJ1

3 0

1 year ago