Answer:
34
explanation:
First of all, put the numbers in order
30, 31, 31, 32, 33, 35, 35, 35, 36, 36
Then, find the middle number.
In this case, there is an even amount of numbers so, we have to pick the 2 middle numbers which is 33 and 35.
Now all you have to do is add these two numbers together then divide by 2 which will give you 34.
or, in simpler questions like this one, you can just say 34 as you know it is between 33 and 35.
In other questions, it might have and odd amount of numbers, for example:
3, 3, 5, 8, 10
so all you would do here is pick the middle number which would be 5. (it has 2 numbers on each side of it)
Answer:
a) 98.522
b) 0.881
c) The correlation coefficient and co-variance shows that there is positive association between marks and study time. The correlation coefficient suggest that there is strong positive association between marks and study time.
Step-by-step explanation:
a.
As the mentioned in the given instruction the co-variance is first computed in excel by using only add/Sum, subtract, multiply, divide functions.
Marks y Time spent x y-ybar x-xbar (y-ybar)(x-xbar)
77 40 5.1 1.3 6.63
63 42 -8.9 3.3 -29.37
79 37 7.1 -1.7 -12.07
86 47 14.1 8.3 117.03
51 25 -20.9 -13.7 286.33
78 44 6.1 5.3 32.33
83 41 11.1 2.3 25.53
90 48 18.1 9.3 168.33
65 35 -6.9 -3.7 25.53
47 28 -24.9 -10.7 266.43
![Covariance=\frac{sum[(y-ybar)(x-xbar)]}{n-1}](https://tex.z-dn.net/?f=Covariance%3D%5Cfrac%7Bsum%5B%28y-ybar%29%28x-xbar%29%5D%7D%7Bn-1%7D)
Co-variance=886.7/(10-1)
Co-variance=886.7/9
Co-variance=98.5222
The co-variance computed using excel function COVARIANCE.S(B1:B11,A1:A11) where B1:B11 contains Time x column and A1:A11 contains Marks y column. The resulted co-variance is 98.52222.
b)
The correlation coefficient is computed as
![Correlation coefficient=r=\frac{sum[(y-ybar)(x-xbar)]}{\sqrt{sum[(x-xbar)]^2sum[(y-ybar)]^2} }](https://tex.z-dn.net/?f=Correlation%20coefficient%3Dr%3D%5Cfrac%7Bsum%5B%28y-ybar%29%28x-xbar%29%5D%7D%7B%5Csqrt%7Bsum%5B%28x-xbar%29%5D%5E2sum%5B%28y-ybar%29%5D%5E2%7D%20%7D)
(y-ybar)^2 (x-xbar)^2
26.01 1.69
79.21 10.89
50.41 2.89
198.81 68.89
436.81 187.69
37.21 28.09
123.21 5.29
327.61 86.49
47.61 13.69
620.01 114.49
sum(y-ybar)^2=1946.9
sum(x-xbar)^2=520.1




The correlation coefficient computed using excel function CORREL(A1:A11,B1:B11) where B1:B11 contains Time x column and A1:A11 contains Marks y column. The resulted correlation coefficient is 0.881.
c)
The correlation coefficient and co-variance shows that there is positive association between marks and study time. The correlation coefficient suggest that there is strong positive association between marks and study time. It means that as the study time increases the marks of student also increases and if the study time decreases the marks of student also decreases.
The excel file is attached on which all the related work is done.
Answer:

Step-by-step explanation:
Given: a graph
To find: the average rate of change of the amount of the element over the 10-minute experiment
Solution:
A rate of change of one quantity with respect to another quantity is known as rate of change. If y is the dependent variable and x is the independent variable then average rate of change = change in y /change in x.
From the graph,
change in x (time) =
minutes
change in y ( amount of the element) =
g
So, average rate of change = 
Answer:
A
Step-by-step explanation:
Hope it helps!
Answers
9(x + y)
(7 - a)(b)
The Distributive Property is used in algebraic expressions to multiply a
single term and two or more terms which are inside a set of parentheses.
In the case of x(2y), there is only
one term inside the parenthesis
In the case of 9(x ∙ y), the distributive
property is not used because (x ∙ y) = xy which means only one term will be
multiplied by the term outside the parenthesis (9)
In the case of 9(x + y), the distributive
property is used because the two terms in the parenthesis (x and y) will be
multiplied by the term outside the parenthesis (9)
9(x + y) = 9*x + 9*y (by applying the distributive property)
In the case of (7 ∙ a)(b), the distributive
property is not used because (7 ∙ a) = 7a which means only one term will be
multiplied by the term outside the parenthesis (b)
In the case of (7 - a)(b), the distributive
property is used because the two terms in the parenthesis (7 and -a) will be
multiplied by the term outside the parenthesis (b)
(7 - a)(b) = 7*b - a*b (by applying the distributive
property)
In the case of (2 ∙ x) ∙ y, the distributive
property is not used because (2 ∙ x) = 2x which means only one term will be
multiplied by the term outside the parenthesis (y)