Question

The table shows the number of flowers in four bouquets and the total cost of each bouquet.

A 2-column table with 4 rows. The first column is labeled number of flowers in the bouquet with entries 8, 12, 6, 20. The second column is labeled total cost (in dollars) with entries 12, 40, 15, 20.
What is the correlation coefficient for the data in the table?

–0.57
–0.28
0.28
0.57

Answer 1

0.28

Work: x̄ = 11.5, ȳ = 21.75.
Sum (xi−x̄)(yi−ȳ) = 65.5, sum (xi−x̄)^2 = 115, sum (yi−ȳ)^2 = 476.75.
r = 65.5 / sqrt(115·476.75) ≈ 65.5 / 234.15 ≈ 0.28.