In a certain appliance store, each model of television is uniquely designated by a code made up of a particular ordered pair of letters. If the store has 60 different models of televisions, what is the minimum number of letters that must be used to make the codes?
I think the official answer supplied by PR is incorrect.
I Feel that D is the correct answer, they say C.
Am I missing something?
If n is the number of distinct letters used to create the two lettered codes, than a total of n * n = n^2
different codes can be created. We need n^2\geq60
. The smallest n which fulfills this condition is n = 8.
PhD in Applied Mathematics
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