Let T = {p, q, r, s, t}. The number of strings in S of length 4 such that no…

2024

Let T = {p, q, r, s, t}. The number of strings in S of length 4 such that no symbols can be repeated. *

  1. A.

    120

  2. B.

    625

  3. C.

    360

  4. D.

    More than one of the above

  5. E.

    None of the above

Attempted by 175 students.

Show answer & explanation

Correct answer: A

To find the number of 4-letter strings from T = {p, q, r, s, t} with no repeated symbols, we calculate the number of permutations of 5 elements taken 4 at a time. This is P(5,4) = 5! / (5-4)! = 120. Therefore, the number of such strings is 120.

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