There is 1 module divided in two parts unequally, 1st part get 50% fail and 2nd get 40% fail then what will be the overall failure of whole module?
Assuming that the module fails if either (or both) of the parts fail, the Probability that both parts will be operational (no failures) is:
Pop = (1-0.5)(1-0.4) = 0.3 = 30%
So the probability that the Module will fail (one or both parts) is:
Pfail = 1 - Pop = 1 - 0.3 = 0.7 = 70%