Many stores run "secret sales": Shoppers receive cards that determine how large a discount they get,but the percentage is revealed by scratching off that black stuff only after the purchase has been totaled at the cash register.The store is required to reveal (in the fine print)the distribution of discounts available.Determine whether the following probability assignment is legitimate.
Probability of ...
A)Legitimate
B)Not legitimate

Question

Many stores run "secret sales": Shoppers receive cards that determine how large a discount they get,but the percentage is revealed by scratching off that black stuff only after the purchase has been totaled at the cash register.The store is required to reveal (in the fine print)the distribution of discounts available.Determine whether the following probability assignment is legitimate.
Probability of ... 
A)Legitimate 
B)Not legitimate

Quizplus · Accepted Answer

The provided probability distribution table does not add up to 1. The sum of probabilities for all of the discount options is only 0.85, meaning there is a 15% chance that none of the available discounts will be used. This is not a legitimate probability distribution since the probabilities must add up to 1.

Many Stores Run "Secret Sales": Shoppers Receive Cards That Determine