Given the three digits 2, 4 and 7, how many different positive two-digit integers can be formed using these digits if a digit may not be repeated in an integer?

3 nPr 2 = 6 permutations.

{2, 4} | {2, 7} | {4, 2} | {4, 7} | {7, 2} | {7, 4} (total: 6)

6. 3 possible digits, 2 digit numbers 2*3=6 also the 2 digit numbers are 24,27,72,74,72,42