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A = {A, B, C, D, E, F, G}

B = {0, 1, 2}

C = {1, 2, 3, 4, 5, 6, 7, 8, 9}

The filing system in an office requires each file to have an alphanumeric code name of the form abc. A, B and C are the sets from which a,b, and c must be chosen. How many possible code names are there?

Correct Answer: 189

Explanation:

We have a choice of 1/7 for a, 1/3 for b and 1/9 for c. Therefore we have 7 x 3 x 9 = 189 possible code names. (You multiply the choices because any one from a set can be combined with any from the other sets)

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