Training Schedule
Why do this problem?
When we watch sports coverage of the multi-discipline events
such as the heptathlon, the scoring mechanism is not usually made
explicit. This problem explores some of the maths behind the
scoring system and invites students to optimise an athlete's
performance by choosing a suitable training schedule. Along the
way, students can practise substituting into formulas, make sense
of functions, and use spreadsheets to repeat routine calculations
quickly.
Possible approach
Set the scene by introducing the seven heptathlon events
(perhaps asking students if they can name the events). Then display
the two equations:
$y=a(b-x)^c$ (1)
$y=a(x-b)^c$
(2)
"These are the equations used to calculate the points scored
in the different heptathlon events. Why do you think there are two
equations? Which equation do you think is used for each
event?"
Give students time to discuss their answers in pairs, and then
share as a class.
Now display the rest of the problem and/or hand out
this worksheet.
Before they get started, take some time to talk through the
problem, and check students understand the task.
As there is quite a bit of repeated computation involved, it
may be useful to use spreadsheets if computers are available.
Alternatively, students could work in small groups and share out
the calculations among themselves.
Finally, gather the class together to share the different
training schedules they have devised.
Key questions
What happens to the number of points given by each equation as
$x$ increases/decreases?
Possible extension
Imagine the heptathlon was to become an octathlon. Choose an
eighth event and design and justify a scoring formula which would
allocate points consistent with the other events.
Possible support
Students may opt to use a calculator to solve this problem, but it
is much more efficient to use a spreadsheet. In order to make the
most of the task, it may be worthwhile spending some time with the
whole class talking about how to set up formulas in a spreadsheet
and how to make changes to investigate different training
schedules.