Answer:
0.0444 = 4.44% probability that a part chosen at random (from the sample) was defective.
Step-by-step explanation:
Probability of a defective part:
0.04 of [tex]\frac{100}{180}[/tex], that is, coming from A.
0.05 of [tex]\frac{80}{180}[/tex], that is, coming from B. So
[tex]p = 0.04\frac{100}{180} + 0.05\frac{80}{180} = \frac{0.04*100 + 0.05*80}{180} = 0.0444[/tex]
0.0444 = 4.44% probability that a part chosen at random (from the sample) was defective.