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Age 11 to 14 Short
Challenge Level

On Aisha's holiday, $11$ days had some rain.

A morning rain was always followed by a clear afternoon.
An afternoon rain was always preceded by a clear morning.

A total of $9$ mornings and $12$ afternoons were clear.

How many days had no rain at all?

This problem is taken from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.