Final answer:
The probability that house A does not sell given that house B does not sell is 0.286 or 28.6%.
Step-by-step explanation:
The student has asked what the probability is that house A does not sell given that house B does not sell. To calculate this, we will use the concept of conditional probability. The formula for the conditional probability of A given B is P(A|B) = P(A and B) / P(B).
Here, let's let A be the event that house A does not sell and let B be the event that house B does not sell. From the information given, we know that P(B) is 70% (since there's a 30% chance that B sells, there's a 70% chance it doesn't). We also know that there is a 20% chance that both A and B do not sell (P(A and B)).
Using the formula, P(A|B) = P(A and B) / P(B), we substitute the known values:
P(A|B) = 0.20 / 0.70 = 0.286 (approximately).
Therefore, the probability that house A does not sell given that house B does not sell is 0.286 or 28.6%.