# Bayesian network- count probability of an event

I'm having hard time figuring out why the probability of $l^1 = 0.502$ (via https://courses.csail.mit.edu/6.034s/handouts/spring12/independencies.pdf)

I'm getting quite lost in computations. Can anybody help in explaining what happened that such probability was derived?

• The computation is somewhat tedious, but as a starter your expression for $p(l^1)$ should be a sum of 12 terms. – tddevlin Jun 27 '18 at 18:35