Step 1 :Given that there are 365 days in a year, the probability that two people selected at random do not have the same birthday is calculated as follows: The first person can have a birthday on any of the 365 days, hence the probability is \(\frac{365}{365}\). For the second person to not have the same birthday, they must have one of the remaining 364 days, hence the probability is \(\frac{364}{365}\). Therefore, the total probability is \(\frac{365}{365} \cdot \frac{364}{365}\).
Step 2 :To find the probability that five people selected at random all have different birthdays, we calculate the probability for each person. The first person can have a birthday on any of the 365 days, hence the probability is \(\frac{365}{365}\). For the second person to not have the same birthday, they must have one of the remaining 364 days, hence the probability is \(\frac{364}{365}\). This pattern continues for all five people, hence the total probability is \(\frac{365}{365} \cdot \frac{364}{365} \cdot \frac{363}{365} \cdot \frac{362}{365} \cdot \frac{361}{365}\).
Step 3 :Calculating the above expression, we find that the probability that five people, selected at random, all have different birthdays is approximately 0.973.
Step 4 :Final Answer: The probability that five people, selected at random, all have different birthdays is approximately \(\boxed{0.973}\).