The resistance of a certain type of electrical resistors has normal distribution with mean of 45 ohms. A random sample of 9 such resistors is selected, and the variance is computed to be 4. What is the probability that the average resistance will exceed 47 ohms?

0.00135

Step-by-step explanation:

When given a random sample of numbers:

z-score is is z = (x-μ)/σ/√n

where x is the raw score

μ is the population mean

σ is the population standard deviation.

Standard deviation = √variance = √4 = 2

Mean = 45 ohms

A random sample of 9 such resistors

z = 47 - 45/2 / √9

z = 2/2/3

z = 3

P-value from Z-Table:

P(x<47) = 0.99865

P(x>47) = 1 - P(x<47) = 0.0013499

Approximately ≈ 0.00135

The probability that the average resistance will exceed 47 ohms is 0.00135

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.

r and t.

both are 64 degrees.