A professor walks into a upper division statistics class and says, "I grade using a bell curve and z-scores. Whatever the range of grades happens to be, I will standardize the curve so that the mean will earn a C grade, and so will people in the range of +/- the class standard deviation. People in the range of one to two standard deviations above the mean will earn a B grade, and people who are above two standard deviations above the mean will earn an A grade. This will be true even if the mean of the class is 40% and the 90th percentile is 60%, which is possible because this class is very hard." Do you think this is a fair application of the normal distribution? Why or why not? Justify your answer using the properties of the normal distribution.

can you give me more detail on this! ?

step-by-step explanation:

true

explanation:

answer

the correct answer is

explanation

the given function is

the excluded values are obtained by solving:

we factor to obtain:

the excluded values are

let's add {f(x)=x+1}f(x)=x+1 and {g(x)=2x}g(x)=2x together to make a new function.

f(x)+g(x) =(x+1)+(2x)=x+1+2x=3x+1

let's call this new function hh. so we have:

{h(x)}={f(x)}+{g(x)}{=3x+1}h(x)=f(x)+g(x)=3x+1

we can also evaluate combined functions for particular inputs. let's evaluate function hh above for x=2x=2. below are two ways of doing this.

method 1: substitute x=2x=2 into the combined function hh.

h(x)

h(2)

​    

=3x+1

=3(2)+1

=7

​ since h(x)=f(x)+g(x)h(x)=f(x)+g(x), we can also find h(2)h(2) by finding f(2) +g(2)f(2)+g(2).

first, let's find f(2)f(2):

f(x)

f(2)

​    

=x+1

=2+1

=3

​  

now, let's find g(2)g(2):

g(x)

g(2)

​    

=2x

=2⋅2

=4

​  

so f(2)+g(2)=3+4=\greend7f(2)+g(2)=3+4=7.

notice that substituting x =2x=2 directly into function hh and finding f(2) + g(2)f(2)+g(2) gave us the same answer!