thebogie17 wrote:

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?

A. 6

B. 7

C. 8

D. 9

E. 10

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, then 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.

Answer C

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PhD in Applied Mathematics

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