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## 'Highs and Lows' printed from http://nrich.maths.org/

I have a max/min thermometer in my greenhouse. It records both the highest and the lowest temperatures reached since the time I reset it.

I reset it on Sunday when the temperature was $4^\circ \text{C}$.

Overnight the temperature fell $5^\circ$.

Then during Monday it rose by $6^\circ$ before falling $10^\circ$ during the night.

On Tuesday it rose by $4^\circ$ and fell by $2^\circ$ overnight.

On Wednesday morning, what were the maximum and minimum temperatures recorded?

*This problem is taken from the UKMT Mathematical Challenges.*

*View the archive of all weekly problems grouped by curriculum topic*