Question

The table shows the average number of hours of daylight per day for the last four months of the year. What is the correlation coefficient for the data in the table?

month of year------------------------------- 9 10 11 12
average hour of day light per day---12,37 11.37 10.57 10
A. -0.993
B. -0.791
C. 0.791
D. 0993

Answer 1

A

Explanation:

edge 2020 Dec 4

Answer 2

(A)

Explanation:

For finding the correlation coefficient (r), we use the formula

r = \frac{n(\sum xy)-(\sum x\sum y)}{\sqrt{n\sum x^2-(\sum x)^2}\sqrt{n\sum y^2-(\sum y)^2}}

We take x as the month of year and y as the average hour of day light per day

n = 4

We have, ∑x = 42, ∑y = 44.37 ,∑xy = 461.3 ∑x^2 = 446, ∑y^2 = 494

r =
`(4(461.3)-(24*44.37))/(√(4(446)-(42)^2)√(4(494)-(44.37)^2)  )`

= - 0.993 (approx)