Why do this problem?
This is one of a series of problems which students might encounter in Food Technology.
originated in a real situation when someone cooked a beautiful meal, only noticing in the last five minutes that the recipe said 'Serve with rice' - by which time it was too late, if the rest wasn't to be ruined.
Mathematically, it gives practice in organising information. The cards provided should be put in order, then a timeline can be drawn up. To put the cards in order, students will need to know, find out or estimate how long some of the operations take.
Do you have all the information you need to put the cards in order? If not, how can you find it?
Will you start your timeline from the beginning of cooking the meal or from the end, working backwards?
Hmm ... when should Tom have put the rice on
is a similar problem, but with more complex recipes to plan.
Let students discuss in groups what information they need but don't have, and see if the group can come up with sensible answers so that they can together put the cards in the right order.