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Decimal Time

Age 11 to 14 Challenge Level:

In France in 1793 decimal time was introduced, then abandoned only two years later.

Look at these pairs of times. The one on the left is our time and the clock on the right shows the corresponding French decimal time.


our time - 16.43, French decimal time 6.54

our time - 12.00, French decimal time - 5.00

Can you decipher how French decimal time works?
How did you use the clocks to help you?


Click here for a poster of this problem.