1/12c = 0.6
To remove a fraction you simply multiply it by its inverse fraction (take the original fraction and flip it! So, multiply it by 12/1 (which is the same as saying 12).
12(1/12c) = 0.6*12
The 12 cancels out leaving this:
c = 0.6 * 12
c = 7.2
If you don't have or are allowed to use a calculator. To compute that you simply make 0.6 into a fraction then multiply the numerator by 12. .6 is in the tenths place so you can write it like this:
6/10 simplifying it becomes, 3/5
3/5 * 12 = 36/5
Now! That was assuming 1/12c was written like this:
(1/12)c = 0.6
If it was actually written like this:
1/(12c) = 0.6 then you'll do this.
Multiply 0.6 by 12c. Which will get you 7.2c. After that you need to get c alone, so you divide both sides by 7.2. Yielding the result:
1/7.2 = c
c = 0.1389...
The answer is 2.
3x+2y=3
2x-2y=7
solve both the equations
3x+2y=3
+2x-2y=7
5x=10
so we get
x=2
Answer:
-6/-2=3 (the answer is 3)
Step-by-step explanation:
Change in y/ Change in x. How you do it: -6-0/2-4=-6/-2=3
Hope this helped :)
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:
21+10.5 which would equal 31.5
Step-by-step explanation: