The average temperature in May is 18 ºC. The average temperature in November is a third of the average temperature in May. The average temperature in September is twice the average temperature in November. What is the average temperature in September?

This question has multiple stages to go through, so firstly we see what they are looking for you to have found by the end of the question, which is the average temperature in September. Looking at the information given, we can see that the temperatures of the months are all related, so we need to work through the problem month by month.

The average temperature in November is a third of the temperature of May, so the first calculation we do is 18/3 = 6. This gives the temperature of November.

Next, we know that the temperature in September is twice that of November, so we multiply the temperature of November (6 degrees) by 2. This gives 2x6 = 12. Therefore, we can see that the average temperature in September is 12 degrees.