In a new book, The Astronaut Selection Test Book: Do You Have What it Takes for Space?, Peake reveals some of the fiendishly difficult puzzles that astronauts have to solve before they are judged suitable to be sent hurtling into space.  

Here’s just one – which could also be useful for all you recruiters who supply staff to zoos, safari parks and circuses…

A keeper at a zoo has food that would last 78 days for seven lions. How long would the food last for 21 lions? *
a) 26 days
b) 30 days
c) 28 days
d) 27 days

Have you got the answer yet? Oh well, as Peake himself said when interviewed on the radio this morning, “8,000 applicants for six jobs, they are not great odds”, so I guess the means justifies the ends.

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* _{Answer: a}