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)
3) The strength is - association.
<u>Solution- </u>
A researcher placed a petri dish with 32,000 bacterial cells. One hour after being placed in the vacuum chamber, the number of cells in the petri dish had halved. Another hour later, the number of cells had again halved.
This can be represented as exponential decreasing function,
Where,
Putting the values,
y-intercept means, where x=0, so
The coordinate of this poin will be (0, 32000)
This means when x=0 or at the starting of the research, the number of bacteria cells was 32000.
After 3 hours, number of bacteria cells will be,
The coordinate of this point will be (3, 4000)
