MCQ
If $^{12}{P_r} = 1320$, then $r$ is equal to
  • A
    $5$
  • B
    $4$
  • $3$
  • D
    $2$

Answer

Correct option: C.
$3$
c
(c) Since $^{12}{P_3} = 1320;\,\,\therefore \,\,r = 3$.

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