Question

pony weigh? Let x be the age of the pony (in months), and let y be the average weight of the pony incom) OBJAR YOUR TEAC X 3 60 6 95 12 14 21 140 150 189 of the data and visualize the line you think best fits the data (a) Make a scatter diagram Graph Layers Clean ► Point 1 *NO? Point 2 Point 3 Point 4 LLLL LLLLLLLLLL Point 5 WebAssign Graphing Tool Submission Data

Answer 1

	x	y	xy	x2	y2
	3	60	180	9	3600
	6	95	570	36	9025
	12	140	1680	144	19600
	14	150	2100	196	22500
	21	189	3969	441	35721
Total	$\small \Sigma x$=56	$\small \Sigma y$=634	$\small \Sigma xy$=8499	$\small \Sigma x^{2}$=826	$\small \Sigma y^{2}$=90446

n: Number pairs of observations = 5

Verified :

ναι, ει: Σ- . Σ - 120. Σν- ι. Σ' - 9ο αιο, κα Σν- Ακου.

Correlation coefficient

$r=\frac{n\Sigma xy-\Sigma x\Sigma y}{\sqrt{ \left [ n\Sigma x^{2} -(\Sigma x)^{2}\right ]\left [ n\Sigma y^{2}-(\Sigma y)^{2} \right ]}}$

$\\=\frac{5\times8499-56\times634}{\sqrt{ \left [5\times826 -(56)^{2}\right ]\left [5\times90446-(634)^{2} \right ]}} \\\\\\=\frac{42495-35504}{\sqrt{ \left [4130 -3136\right ]\left [452230-401956 \right ]}} \\\\\\=\frac{6991}{\sqrt{ 49972356 }} =0.98895012\approx 0.989$

r=0.989