Answer: А. On average, the number of students going to an office hour varies from the mean by about 2.2 students
Step-by-step explanation:
The standard deviation is a measure of spread, which gives how values deviate from the average or mean value of a particular distribution. Hence, the standard deviation is usually defined about the average value of a distribution.
Therefore, for a certain random variable representing the number of student who visits office hours, the standard deviation will be defined about the average or mean value of the random variable Q.
Thus, stated as ; number of students going to an office hour varies from the mean by 2.2 on average.
<span>1/r + 2/1-r = 4/r^2
1-r+2r/r(1-r)=4/r^2
(1+r)/r(1-r)=4/r^2 cancle r both side
1+r/1-r=4/r
cross multiply
r+r^2=4-4r
r^2+4r+r-4=0
r^2+5r-4=0
r^2+4r+r-4=0
solve it for r factor it...
</span>
Marie states that any integer greater than 4 will always get an even number of factors.
This can be proven wrong by (for example) 12.
12 has these factors:
1 x 12
2 x 6
3 x 4
12 has an ODD number of factor pairs.
Another example is 28.
28:
1 x 28
2 x 14
4 x 7
28 has an odd number of factor pairs.
I hope this helps!