1. The total screen time spent on computers, smart devices, video games, and TV/movies tend to increase with age among children.

However, higher screen time is associated with lower psychological well-being such as less curiosity, lower self-control, and worse emotional stability. The negative effects of screen time is more serious for preschoolers (ages 2–5). In a large national survey on screen time, researchers found that the daily screen time for 2- to 5-year-old children was normally distributed with a 1.72 hours. What proportion of preschoolers have daily screen time less than 2 hours?