In how many ways can 5 keys be put in a ring - Vidyadip

MCQ

In how many ways can $5$ keys be put in a ring

✓
$\frac{1}{2}4!$
B
$\frac{1}{2}5\,!$
C
$4\,!$
D
$5\,!$

✓

Answer

Correct option: A.

$\frac{1}{2}4!$

a
(a) Required number of ways = $\frac{1}{2}(5 - 1)\;! = \frac{{4\;!}}{2}$.

{Since clockwise and anticlockwise are same in case of ring}.

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