Answer:
44
Step-by-step explanation:
A set of data has a normal distribution with a mean of 5.1 and a standard deviation of 0.9. Find the percent of data between 4.2 and 5.1.
Answer: The correct option is B) about 34%
Proof:
We have to find ![P(4.2](https://tex.z-dn.net/?f=%20P%284.2%3Cx%3C5.1%29%20)
To find
, we need to use z score formula:
When x = 4.2, we have:
![z = \frac{x-\mu}{\sigma}](https://tex.z-dn.net/?f=%20z%20%3D%20%5Cfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%20)
![=\frac{4.2-5.1}{0.9}=\frac{-0.9}{0.9}=-1](https://tex.z-dn.net/?f=%20%3D%5Cfrac%7B4.2-5.1%7D%7B0.9%7D%3D%5Cfrac%7B-0.9%7D%7B0.9%7D%3D-1%20)
When x = 5.1, we have:
![z = \frac{x-\mu}{\sigma}](https://tex.z-dn.net/?f=%20z%20%3D%20%5Cfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%20)
![=\frac{5.1-5.1}{0.9}=0](https://tex.z-dn.net/?f=%20%3D%5Cfrac%7B5.1-5.1%7D%7B0.9%7D%3D0%20)
Therefore, we have to find ![P(-1](https://tex.z-dn.net/?f=%20P%28-1%3Cz%3C0%29%20)
Using the standard normal table, we have:
= ![P(z](https://tex.z-dn.net/?f=%20P%28z%3C0%29%20-%20P%28z%3C-1%29%20)
![=0.50-0.1587](https://tex.z-dn.net/?f=%20%3D0.50-0.1587%20)
or 34.13%
= 34% approximately
Therefore, the percent of data between 4.2 and 5.1 is about 34%
X would be 63, Y would be 27
A straight line is 180 degrees. 180-117=63
To find Y, since we know it is a 90 degree angle do 90-63 which is 27.
To solve this, what you will need to do is find the solution of one variable and then substitute it and solve for the other.
Here’s how to solve:
y+2x=4
-2x -2x
y=4-2x
4-2x + 2x =4
4=4
So if you’re trying to see if it is true, then your answer is that it’s true.
If you’re trying to find the linear equation, then your answer is y=-2x+4.
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