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Dublin: 0°C Thursday 8 December 2022

# Maths Week: Thursday's puzzle of the day

## We’re setting you a little brainteaser each day this week to highlight a drive to improve the country’s numeracy skills.

Image: brushing teeth via Shutterstock

ENGAGE THOSE BRAINS, folks: we have a teasing question for you.

Each afternoon this week, we’ll be setting you a (not too) tough riddle to get the cogs whirring and test your mathematical mettle.

If this prospect fills you with either a. joy, or b. dread, the mathsweek.ie site is worth a look – with events for maths fans and for those who might feel the need to brush up on their numeracy skills. The events are running from now until Sunday.

Thursday’s puzzle:

I realised that I take around 60 seconds to brush my teeth and I’m in the habit of leaving the tap running. I measured that the tap will fill a 2-litre jug in 16 seconds. I decided to just allow the water to flow while I was rinsing the brush and my mouth. I could accomplish this in 10 seconds.

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Assuming that I brush my teeth twice a day at home, how much water will I save in a year?

### Poll Results:

4,562.5 litres per year (2282)
2,757 litres per year (499)
3,230 litres per year (459)
3,874.75 litres per year (267)

All answers will be revealed tomorrow afternoon. You’ll see what other readers are thinking when you make your choice above and the pie chart shows the most popular option. (We’re not saying that the most popular will be the right one!)