Today Puzzle #665
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Puzzle No. 665 – Thursday 24 January
When Big Ben's bongs are back as before building began, every hour the first strike will sound exactly on the hour. If it takes 9 second to strike 3 o'clock, what time would it be it if it takes 36 seconds to strike?
Today’s #PuzzleForToday has been set by Dr Amanda Turner, Senior Lecturer in Mathematics and Statistics at Lancaster University
Click here for the answer
9 o'clock. At 3 o'clock there are 2 gaps between the 3 strikes, so each gap lasts 4.5 seconds. If it takes 36 seconds to strike then there must be 36/4.5=8 gaps, which means there must be 9 strikes.
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