X is normally distributed with mean 250 and standard deviation 40. what value of x does only the top 15% exceed?

1 answer:

3 0

The top 15% (85th percentile) is the cutoff value $x$ such that

$\mathbb P(X\le x)=\mathbb P\left(\dfrac{X-250}{40}\le\dfrac{x-250}{40}\right)=\mathbb P(Z\le z)=0.85$

where $z$ is the corresponding cutoff for the standardized normal distribution. We have $z\approx1.0364$ , and so

$\dfrac{x-250}{40}=z\implies x\approx291.456$

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8_murik_8 [283]

Answer:

See explanation below.

Step-by-step explanation:

The equation is:

y = 7x + 6

This is the equation of a line in slope intercept form. The general form, where m is the slope and b is the y intercept is:

y = mx + b

In this case, with the equation:

y = 7x + 6

m is 7 and the y intercept is 6.

The y intercept means the point when x = 0:

(0, 6) is the y intercept point on the graph.

Hope this Helps! Have an Awesome Day!! (-:

8 0

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Which of the following best describes the change in the mean when 3 is included in the data set below? 34, 75, 26, 81, 65, 38, 4

kati45 [8]

Answer:

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Step-by-step explanation:

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2 years ago

Please assist me with these problems

Vinil7 [7]

Part (a)

<h3>Answer: y1 and y3 are perpendicular</h3>

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=====================================================

Part (b)

Graph each line to see where they cross. The three points of intersection are

(0,4)

(2,-2)

(4,2)

The order of the points doesn't matter.

You could also form three systems of equations pairing up the equations, and solving each system. That way you can find the points of intersection. Graphing may be a better and faster route in my opinion. See the diagram below.