Calculate Karl Pearson’s Coefficient of correlation from the following data and interpret its value:
Example 1
Calculate Karl pearson's Cofficient of correlation form the followng data and interpret its value:

Price:X	10	12	14	15	19
Supply:Y	40	41	48	60	50

Find the Karl Pearson coefficient of Correlation between X and Y from the following data:

X:	10	12	13	16	17	20	25
Y:	19	22	26	27	29	33	37

Given the following data on sales (in thousand units) and expenses (in thousand rupees) of a firm for 10 month.

Month	J	F	M	A	M	J	J	A	S	O
Sales:	50	50	55	60	62	65	68	60	60	50
Expenses	11	13	14	16	16	15	15	14	13	13

a) Make a Scatter Diagram
b) Do you think that there is a correlation between sales and expenses of the firm? Is it positive or negative? Is it high or low?

The data on price and quantity purchased relating to a commodity for 5 months is given below: Find the Pearsonian correlation coefficient between prices and quantity and comment on its sign and magnitude.

Month	January	Febuary	March	April	May
Prices (Rs):	10	10	11	12	12
Quantity (Kg):	5	6	4	3	3

The height of a child increases at a rate given in the table below. Fit the straight line using the method of least-square and calculate the average increase and the standard error of estimate.

Month	1	2	3	4	5	6	7	8	9	10
Height:	52.5	58.7	65	70.2	75.4	81.1	87.2	95.5	102.2	108.4