Answer:
a) 0.0125
b) 0.4579
Step-by-step explanation:
For this question use tree diagram method to solve the question or by simply listing down the probabilities as I have done in the attached picture. Firstly, we need to convert all percentages in to decimal and those decimals will represent probability of each event. For example if we consider probability of quality score A it can be found by diving 77 with 100:
77/100 = 0.77
Similarly all probabilities can be found by simply dividing percentages with 100.
Part (b) is a conditional probability question. Given that a circuit failed is the condition. So we need to use conditional probability method to solve it.
