Question

Given the four digits 2, 4, 6, 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?

Answer 1

Answer: 12

Step-by-step explanation:

Given the question :

Given the four digits 2, 4, 6, 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?

The number of different positive two integer number can be obtained by:

P(4, 2) = 4P2

Recall:

nPr = n! / (n - r)!

4P2 = 4! / (4 - 2)!

4P2 = 4! / 2!

4P2 = (4 * 3 * 2 * 1) / ( 2 * 1)

4P2 = 24 / 2

4P2 = 12

Hence, 12 different positive two-digit integers can be formed using these digits if a digit may not be repeated in an integer