The table shows the time, to the nearest minute, spent waiting for a taxi by each of 80 people one Sunday afternoon.
Waiting time
(in minutes)
Frequency
\(2 - 4\)
15
\(5 - 6\)
9
7
6
8
24
\(9 - 10\)
14
\(11 - 15\)
12
Write down the upper class boundary for the \(2 - 4\) minute interval.
A histogram is drawn to represent these data. The height of the tallest bar is 6 cm .
Calculate the height of the second tallest bar.
Estimate the number of people with a waiting time between 3.5 minutes and 7 minutes.
Use linear interpolation to estimate the median, the lower quartile and the upper quartile of the waiting times.
Describe the skewness of these data, giving a reason for your answer.