P (B₇₁)

P (B₇₂)

P (B₇₁,B₇₂)

0

0

0*0 = 0

0.3

0.1

0.3*0.1 + 0.1*0 = 0.03

0.3

0.4

0.3*0.5 + 0.4*0.3 = 0.27

0.3

0.3

0.3*0.8 + 0.3*0.6 = 0.42

0.1

0.2

0.1*1 + 0.2*0.9 = 0.28