Are you all listening very carefully?
While I was waiting for my student to finish a question sheet yesterday morning I noticed our facts and figures poster had “How to convert centigrade to Fahrenheit” and vice versa. I seem to remember several times coming across people who couldn’t remember what to do, so here goes:

Temperature in centigrade X 9 divided by 5 + 32
(Our stupid computer doesn’t have a division sign!)
To go the other way:
Temperature in Fahrenheit – 32 X 5 divided by 9

This means the temperature I gave the other day of 42.5°C is 108.5 °F. Please note that our thermometer is against a white wall and therefore gets pretty hot when the sun reaches it. Locally, the temperature has been up to 30°C (86°F).