#05 Murphy鈥檚 law of socks
I am convinced that my washing machine eats socks. Every time I wash a load, another sock disappears. Last week I ran out of socks so I bought myself three new pairs.
What is the chance that, after my first three washes, I will be left with three odd socks? Indeed, what is the chance I will even have one pair intact?
Answer next week
#04 Which door Solution
On a game show, Nico chose three doors out of five, hoping to pick the one hiding a prize. The host then opened three doors, including two of Nico鈥檚, none with the prize. When Nico phones his friend Leah, he asks if he should stick with door B, his original choice, or switch to C. Which door should Leah suggest and what should Nico do?
It doesn鈥檛 matter which door Leah suggests, she has no information to differentiate between the two, so from her point of view the prize is equally likely to be behind B or C.
But to maximise his chance of winning, Nico should stick with door B regardless of what Leah says. There is a 60 per cent chance that the prize is behind door B, and only 40 per cent chance it is behind door C.
Why? Nico had a 60 per cent chance of picking the prize when he chose three out of five doors. In opening three doors that she knew had no prize, the host revealed no new information, and the probability therefore didn鈥檛 change.
Quick quiz #05
1 White-nose syndrome is a fungal disease that has wiped out large numbers of which flying animals in North America?
2 Hanford, in Washington state, and Livingston, in Louisiana, house the detectors for which physics megaproject?
3 What network of membranous tubules is responsible for manufacturing and packaging up proteins in most eukaryotic cells?
4 What acronym refers to the binary strings, originally 7-bit, used since 1963 to encode individual text characters in electronic communications?
5 Daltonism, named after the English chemist John Dalton who did early research into it, is a form of what?
Answers below
Quick quiz #05
Answers
1 Bats
2 The Laser Interferometer Gravitational-Wave Observatory, or LIGO
3 The endoplasmic reticulum
4 ASCII (American Standard Code for Information Interchange)
5 Colour blindness
Answer to last week鈥檚 bonus connection question: Viking, Dover, Sole, Shannon, Portland and FitzRoy are all areas in the UK shipping forecast
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