Answer:
Approximately 1.9 standard deviation below mean.
Explanation:
We have been given that the typical amount of sleep per night that adults get has a bell-shaped distribution with a mean of 7.5 hours and a standard deviation of 1.3 hours. Last night you slept for 5 hours.
We will use z-score formula to solve our given problem as z-score tells that a data point is how many standard deviation above or below mean.
, where,
z = z-score,
x = Sample score,
= Mean,
= Standard deviation.



Therefore, you are approximately 1.9 standard deviation below mean.