In the table above, what is the least number of table entries that are needed to show the mileage between each city and each of the other five cities?
Sorry for the messy picture..
Total number of entries 6*6(6rows*6columns) =36
Now 6 entries are representing mileage with the city itself so subtract that => 36-6
Minimum entries required = half the Total = 30/2 = 15
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