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Decimal Time

Age 11 to 14
Challenge Level


Congratulations to all of you who correctly gave the solution to this problem. There are too many of you to list here.


Harry of CPS was the first to send in a correct answer.

In decimal time the time only goes up to 10 so halfway through our day it is 12.00 and halfway through their day it is 5.00

A team from Oatlands Junior School went on to explain why 15:43 our time is 6:54 French Decimal Time.

In one UK day there are 24 hours, but for the French time there are 10 units of time.
And also for 1440 minutes the French equivalent would be 1000 French mins.
1 minute (English)= 1000 minutes (French)/ 1440 which was 0.6944.


They go on to work out how many minutes past midday (5:00 French Decimal Time) is equivalent to 15:43



The English clock moved 3hrs 43mins (223 minutes) We multiplied 0.6944 by 223 mins to get the French equivalent which was 154.86 French minutes. So the French clock moved 154.86 French minutes to get to 6:54.