If you were to ask 2370 people how many would perfer oranges

A study was designed to investigate the effects of two variables, (1) A student's level of mathematical anxiety and (2) teach

Mashcka [7]

Answer:

$P(X>400)=P(\frac{X-\mu}{\sigma}>\frac{400-\mu}{\sigma})=P(Z>\frac{400-440}{20})=P(z>-2)$

And we can find this probability using the complement rule:

$P(z>-2)=1-P(z$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(z>-2)=1-P(z$

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 scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(440,20)$

Where $\mu=440$ and $\sigma=20$

We are interested on this probability

$P(X>440)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X>400)=P(\frac{X-\mu}{\sigma}>\frac{400-\mu}{\sigma})=P(Z>\frac{400-440}{20})=P(z>-2)$

And we can find this probability using the complement rule:

$P(z>-2)=1-P(z$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(z>-2)=1-P(z$

6 0

3 years ago

If ( f ∘ g)(x) = x2 - 6x + 8 and g(x) = x - 3, what is f(x)?

DochEvi [55]

$\bf \begin{cases}
(f\circ g)(x)=x^2-6x+8\\\\
(f\circ g)(x)=f(~~g(x)~~)\\\\
g(x)=x-3\\
\end{cases}
\\\\\\
\textit{now, one probability is }x^2-1
\\\\\\
f(x)=x^2-1\implies f(~~g(x)~~)=(x-3)^2-1
\\\\\\
f(~~g(x)~~)=(x^2-6x+9)-1\implies f(~~g(x)~~)=x^2-6x+8$

5 0

3 years ago

What is the area of a circle with a radius of 21 feet?

lidiya [134]

Answer:

Area is about 1520.53

Step-by-step explanation:

$A=\pi r^{2}$

A = $\pi 21^{2}$

A ≈ 1520.53

6 0

3 years ago

Which choice best reflects the overall sequence of

Grace [21]

Correct option is D. An unexpected result occurs during the initial phase of a study; the study is modified in response to this result and the results are interpreted and evaluated.

The writer begins this passage by stating that the ability of birds to fly has long been a source of debate among scientists.

The article then goes on to explain that when a group of students challenged Ken Dial to come up with new data on this hotly debated topic, he devised an experiment to study the evolution of flight by observing how baby Chukars learn to fly. Dial noted the unusual way the little Chukar "used its wings and legs cooperatively" to climb over hay bales during the experiment. Following that, he devised a series of experiments to investigate his discovery.

<h3>Below is the passage mentioned in the question is from Thor Hanson, Feathers by Thor Hanson - </h3>

" At field sites around the world, Ken Dial saw a

pattern in how young pheasants, quail, tinamous,

and other ground birds ran along behind their

parents. “They jumped up like popcorn,” he said,

5 describing how they would flap their half-formed

wings and take short hops into the air. So when a

group of graduate students challenged him

to come up with new data on the age-old

ground-up-tree-down debate, he designed a project

10 to see what clues might lie in how baby game birds

learned to fly.

.............................................................

Ken called the technique WAIR, for wing-assisted

incline running, and went on to document it in a

wide range of species. It not only allowed young

birds to climb vertical surfaces within the first few

weeks of life but also gave adults an energy-efficient

65 alternative to flying. In the Chukar experiments,

adults regularly used WAIR to ascend ramps steeper

than 90 degrees, essentially running up the wall and

onto the ceiling.

In an evolutionary context, WAIR takes on

70 surprising explanatory powers. With one fell swoop,

the Dials came up with a viable origin for the

flapping flight stroke of birds (something gliding

animals don’t do and thus a shortcoming of the

tree-down theory) and an aerodynamic function for

75 half-formed wings (one of the main drawbacks to the

ground-up hypothesis). "

To learn more about passages from the given link

brainly.com/question/27860285

#SPJ4

7 0

1 year ago

Casey is dividing x3 - 2x2 - 10x + 21 by x2 + x - 7 using a division table. His work is shown here. What is the value of A? –3 –

bearhunter [10]

Answer:-3

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers