Final answer:
The average person needs 7 to 9 hours of sleep per night to prevent sleep debt, with this requirement decreasing from 12 to 18 hours for newborns to 7 to 9 hours for adults.
Step-by-step explanation:
The average adult needs 7 to 9 hours of sleep per night to avoid accumulating a sleep debt. This finding is supported by research from the National Sleep Foundation and various studies indicating that sleep needs decline with age. Newborns require the most sleep, ranging from 12 to 18 hours, which reduces to about 7 to 9 hours by adulthood. As people often sleep less than the recommended amount, especially in their college years, they accrue sleep debt, which can impact alertness and mental efficiency.