There is quite a lot of information in this problem to digest. Students might need to spend some time reading through the problem and making sense of the data. It would work best as a homework or task where students are given time to think about the problem and then to come up with their own analysis. Students could then compare their answers at a later time. From these, the concensus for a 'best' analysis might emerge.

Before starting this problem, how might we organise or represent the data? Are you clear as to how we might test the hypothesis?

This question naturally raises its own extension: students might try to improve their answers by searching for more data on in the internet. pose their own questions, make their own hypothesis or pursue similar ideas through the materials on the Understanding Uncertainty site.

Suggest students simply make plots of the life expectancy data and extrapolate these graphs.