Friday puzzle, no.20 (on time edition)

In an interesting break with tradition, this week’s Friday Puzzle is brought to you on a Friday.

First, the answer to last week’s puzzle:

Assuming that there are nearly 7,000,000,000 (7 billion) people on Earth, estimate the size of number you’d get if you multiplied together the number of fingers on everyone’s hands. For this calculation, it might be easier to count a thumb as a finger. How many zeroes would this number have? How many beaches of sand would this be? How far into the galaxy could we reach if your answer was converted to miles? How many zebras would you need to have this many hairs?

The answer, of course, was zero. The man who puts this puzzle together, my good friend Wrighty, is a cad, isn’t he?

Whilst the answer to that seemingly complex puzzle was simple, the answer to this week’s seemingly simple puzzle is, I suspect, complex (puzzle courtesy of Brainbashers:

Fred Smith bought a used car for £4,000 and sold it to Alice for £5,000. Fred later bought it back for £6,000 and then resold it to Alan £7,000. How much profit did Fred make?

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Man of letters & numbers; also occasionally of action. Husband to NTW. Dad of three. Friendly geek.

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