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.

Monday’s puzzle:

A cash collection was made around a room with everyone putting a note into a bag. People put in either a €20, a €10 or a €5 note.

I asked the collector how much was in the collection and he told me that if I pulled out a note at random that there would be a 1 in 12 chance of getting a €20 note. He said there would be a 1 in 4 chance of getting a €10 note and a 2 in 3 chance of getting a €5.

I protested that I needed more information. He conceded that four people had put in €20 notes and he refused to tell me any more.

Can you figure out how much money was in the bag?

All answers will be revealed on Friday 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!)

These handy tips will help develop your child’s maths skills (without them knowing it)>

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