|[home] [lexicon] [problems] [tests] [courses] [auxiliaries] [notes] [staff]|
Solution to the problem of the (previous) week
Problem:During a day, the display of a digital watch shows different times consisting of digits each, that is digits altogether:
How many times does each of the digits occur?
Solution:We regard the four digits on the display separately.
The digits 0 and respectively appear each for ten hours times and the digit for four hours times
Each of the digits are to be seen for three hours times All the other digits do not appear between 20:00 and 23:59. They are displayed only times
Here, only the digits appear, and all of these for the same number of times, that is times
All the digits appear times
To sum up we can compile the following table: