Final answer:
The probability of both items being returned for a refund by a mail-order company, when 5% of items are typically returned, is found by multiplying the probability of each independent event, resulting in a combined probability of 0.25% or 0.0025.
Step-by-step explanation:
To find the probability that two items sold by a mail-order company will both be returned for a refund, we must consider each sale as an independent event. Given that 5% of items, or 0.05 as a probability, are returned, we're looking for the probability of both events happening back-to-back. Therefore, we multiply the individual probabilities:
Probability of first item being returned = 0.05
Probability of second item being returned = 0.05
To find the combined probability of both items being returned, we multiply the two probabilities:
P(both items returned) = 0.05 × 0.05 = 0.0025.
So, the probability that both items sold during a given hour will be returned for a refund is 0.0025, or 0.25%.