Is it cold outside? Yes! The fire warm? Yes! Snow on its way? Yes! Do we love Christmas? YES! Celebrate the countdown with the Plus advent calendar featuring our favourite bits of maths. Now, what's behind today's door...?
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My son loves the Math advent calendar, but sadly I can't open nr 11. All other days are accessible but nr 11 gives an error message saying I am not authorised. Could you please allow access to all days?