Counter catastrophe

The ability to read a set of statements analytically is an essential skill. Logic problems like this require students to use their “reading with understanding” skills to sift through the information and sort the statements into a logical order from which they can draw conclusions.

Note that the answer is not obvious on a first reading. The information has to be read several times before all the links can be made. A discussion about how detectives solve crime may be helpful. The clues are examined over and over again before the links become clear.

The most difficult task is deciding where to start and what strategy to use. A table, as suggested in the activity and shown in full below, is often a good approach to logic problems because the process of completing the table requires the student to sift and organise the facts.

Once the table has been created, the student can examine the clues and record positive and negative links on the table, using ticks and crosses or question marks. Especially at the start of the process, it is just as important to know what a particular person definitely does not do as it is to know their speciality.

The clues:

1. Both Chinda and Alec work with water. For one, it is always the problem; for the other, it is usually part of the solution.
2. In built-up areas, Piri’s emergencies can cause Chinda’s emergencies.
3. Water is always a factor in Latu’s emergencies; sometimes it is for Hawke, too.
4. Piri’s emergencies can cause much more widespread destruction than Hawke’s.

Clue 1

This clue tells us that Chinda and Alec deal with fires and floods. (Although it is true that water is a factor in other types of emergencies, such as shipwrecks, floods are the only emergency in which, by definition, water is always the problem.) We can summarise our deductions at this point with the following table:

Clue 2

Piri can’t be the shipwreck person because shipwrecks won’t cause a problem in built-up areas. Also, we know from the first clue that Piri is not the fires or floods person, so the question is whether he is the aircraft or earthquakes person. Either type of emergency is more likely to cause a fire than a flood in a built-up area, so fires could be Chinda’s  specialty, which leaves floods to Alec:

However, earthquakes can also result in flooding (for example, if a dam bursts near a built-up area), so it could also be that Chinda is the floods person, leaving fires to Alec.

Clue 3

Given that Chinda and Alec are the fire and floods people, there is only one other type of emergency in which water is always a factor, and that is shipwrecks, so these must be Latu’s responsibility. This leaves us with aircraft and earthquake emergencies to be allocated between Piri and Hawke:

Clue 4

Earthquakes can cause more widespread destruction than aircraft emergencies, so Piri must be the earthquakes expert and Hawke the aircraft emergencies expert:

Many students thrive on problems like these once they get a taste for them. Most bookshops sell inexpensive logic puzzle books that can be used as a classroom resource for improving analytical reading strategies.

A possible answer is:

• Chinda: fires
• Hawke: aircraft emergencies
• Piri: earthquakes
• Latu: shipwrecks
• Alec: floods

You could also justify Chinda as floods and Alec as fires.