To get Row 5, we square everything in Row 4:

x	50	150	250	350	450
P(X = x)	.1	.3	.2	.4	0
x.P(X = x)	5	45	50	140	0	= Sum = 240
x-	-190	-90	10	110	210
(x- )2	36100	8100	100	12100	44100
(x- )2.P(X = x)	.1 36100 = 3610	.3 8100 = 2430	.2 100 = 20	.4 12100 = 4840	0 44100 = 0	2 =Sum = 10900

Just close this window to return to the tutorial.