Monty Hall

S our younger son is an avid reader, fiction, non fiction, topical news items, everything. It is rare that you will discuss a subject where he already does not have an insight and in addition he will often bring up in conversation an item that has captured his attention.
At the weekend he brought to our attention the Monty Hall problem. It is a mathematical model dressed up in TV panel game format but the precise and correct logic defies initial human intuition. After he explained it I had to go away and think hard about it for myself. I can't just accept something like this without the mathematical proof. I am happy about it now. (I managed without the youtube explanation) 

The Monty Hall Problem

Entirely unrelated, this is a phone picture from our work site today.

Apologies to all for the confusing typo (now corrected)
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