Answer:
a. 0.75
b. 0.5526
c. 0.1974
Step-by-step explanation:
Probability is typically expressed as a fraction where the numerator is the number of desired outcomes and the denominator is the total number of outcomes. In this case the suitable parts is the desired outcome and the total shipment is the total parts:
The probability the both the first and second part are suitable:
Since the probability of getting a suitable part the first time is 15/20, then there is one less suitable part and one less part overall to choose on the second time, or 14/19.
Lastly, the probability of choosing a suitable part the first time is again 15/20, but the second part not being suitable would be 5/19: