The lengths of time in minutes to swim a certain distance by the members of a class of twelve 9-year-olds and by the members of a class of eight 16-year-olds are shown below. 9-year-olds: 13.0 16.1 16.0 14.4 15.9 16-year-olds: 14.8 13.0 11.4 11.7 15.1 14.2 13.7 16.7 16.4 15.0 13.2 16.5 13.7 12.8 12.9 (i) Draw a back-to-back stem-and-leaf diagram to represent the information above. [4] (ii) A new pupil joined the 16-year-old class and swam the distance. The mean time for the class of nine pupils was now 13.6 minutes. Find the new pupil's time to swim the distance. [3]