Final answer:
The mean number of No-Shows in a scientific study with 80 hotel reservations is 8.
Step-by-step explanation:
To calculate the mean number of No-Shows, we need to multiply the percentage of No-Shows by the total number of hotel reservations. Since 10% of people don't show up, the percentage of No-Shows is 0.10. The total number of hotel reservations is 80. Therefore, the mean number of No-Shows is 0.10 * 80 = 8.