A large number of children were surveyed. The table below shows the distribution of the time they spent watching TV in the week before the survey. Intervals include the left endpoint but not the right. You can assume that the times are uniformly distributed within each interval. The table is used to draw a histogram of the distribution.
time (hours) percent
0-4 28
4-8 36
8-12 12
12-20 12
20-28 12
Find the height of the bar over interval 4-8, in percent per hour. Please do not enter units of measurement.
Estimate the 80th percentile of the distribution of times, in hours; give the best estimate you can, based on the information in the problem. Please do not enter units of measurement.