Answer:
1) The linear regression model is y = -0.0348·x + 13.989
2) The correlation coefficient is -0.0725
3) The strength of the model is strong - association
Step-by-step explanation:
1)
X Y XY X²
27 13 351 729
65 12 780 4225
83 11 913 6889
109 10 1090 11881
142 9 1278 20164
175 8 1400 30625
∑ 601 63 5812 74513
From y = ax + b, we have
b = 1/n(∑y -a∑x) = 1/6(63 - (0.0348)×601) = 13.989
Therefore, the linear regression model is y = -0.0348·x + 13.989
2)
![r = \frac{n\sum xy - \sum x\sum y }{\sqrt{[n\sum x^{2}-\left (\sum x \right )^{2}] [n\sum y^{2}-\left (\sum y \right )^{2}]}} = \frac{6 \times 5812 - 601 \times 63}{\sqrt{[6 \times 74513-601^{2}] [6 \times 3969 - 63^2]} } = - 0.0725](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7Bn%5Csum%20xy%20-%20%5Csum%20x%5Csum%20y%20%7D%7B%5Csqrt%7B%5Bn%5Csum%20x%5E%7B2%7D-%5Cleft%20%28%5Csum%20x%20%20%5Cright%20%29%5E%7B2%7D%5D%20%5Bn%5Csum%20y%5E%7B2%7D-%5Cleft%20%28%5Csum%20y%20%20%5Cright%20%29%5E%7B2%7D%5D%7D%7D%20%20%3D%20%5Cfrac%7B6%20%5Ctimes%205812%20%20-%20601%20%5Ctimes%2063%7D%7B%5Csqrt%7B%5B6%20%5Ctimes%2074513-601%5E%7B2%7D%5D%20%5B6%20%20%5Ctimes%203969%20-%2063%5E2%5D%7D%20%7D%20%3D%20-%200.0725)
3) The strength is - association.
The equation will be 6x + x where 6x refers to gray and x refer to white
The area of the bedroom is 30cm^2. Since 5m is 10 cm, 15m is 30cm.
Your answer is 15 square meters
Its not 70 its 56, because you have to see how many minutes it takes for 1 to do 4 walls which would be 40*8.
Then you have to see if how many minutes its take a person to do one wall which is 8*40/4 from getting the amount of the 1 person doing 4 walls and get 80.
Then you need to see how many walls a person can paint 7 walls out of 10 people.So, we know how many minutes for each wall which is 80 and then multiply it by 7 to get 560 and divide it by 10 to get a product of 56.
