Again we have two methods, A and B, available for teaching a certain industrial skill. There is an 80% chance of successfully learning the skill if method A is used, and a 95% chance of success if method B is used. However, method B is substantially more expensive and is therefore used only 25% of the time (method A is used the other 75% of the time).

What is the probability that a randomly chosen worker will learn the skill successfully?

P(L) = .75 * .80 = .60

P(L) = .25 * .95 = .2375

P(L) = .75 * .25 + .80 * .95 = .9475

P(L) = .75 * .95 + .25 * .80 = .9125

P(L) = .75 * .80 + .25 * .95 = .8375