russ9 wrote:
Bunuel wrote:
C^2_30 is choosing 2 out of 30. There are 30 cities and each pair of cities need an entry, hence 30 cites need C^2_30 entries.
Hope it's clear.
Hi Bunuel,
Unfortunately, still not clear. Why are we choosing2 out of30?
Consider the table given in the original post:
A and C have 1 entry;
A and D have 1 entry;
A and E have 1 entry;
B and C have 1 entry;
B and D have 1 entry;
B and E have 1 entry;
C and
...
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