Suppose a student just found out that she scored a 75 on her first statistics exam, with a z-score of 0.5. Her friend, who is in a different section with the same professor, also scored a 75 but had a z-score of −0.5. What can you conclude about the mean exam scores in the two classes?

The mean exam scores in the second section is greater than the mean exam scores in the first section

Step-by-step explanation:

Here, we are interested in making a conclusion.

Mathematically;

z-score = (score - mean)/SD

so basically, what determines the sign of the z-score is dependent entirely on the mean.

If the mean is larger than the score, we will have a negative z-score. If the mean is smaller than the score, then will have a positive z-score

So basically what drives the sign is the mean value since the scores are the same for both students in this case, irrespective of the standard deviation in both classes.

So, for the first girl with a positive z-score, we can conclude that her score is larger than the mean; while for the second girl with a negative z-score, her score is smaller to the mean.

Thus, what we conclude here is that the mean score of the second section with the professor is greater than the mean score of the first section with the professor.

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'.

25 questions , because they start with 100.  

350-100=250 .  

. 250/10=25

step-by-step explanation:

first take off 100, then what x 10 = 250? that is your answer. (25)