Final answer:
To determine the probability that Harold buys an ice-cream on Wednesday, we consider the probabilities for each day. Given that he bought an ice-cream on Monday, there is a 40% chance that he will buy an ice-cream on Wednesday.
Step-by-step explanation:
To determine the probability that Harold buys an ice-cream on Wednesday, we need to consider the probabilities for each day.
Given that he bought an ice-cream on Monday, there is a 30% chance that he will buy a drink on Tuesday and a 40% chance that he will buy an ice-cream on Tuesday.
Using the probabilities, we can calculate the probability that Harold buys an ice-cream on each day:
Monday: 1 (since he bought an ice-cream)
Tuesday: 0.4 (40% chance of buying an ice-cream based on previous ice-cream purchase)
Wednesday: 0.4 (40% chance of buying an ice-cream based on previous ice-cream purchase)