Ten persons, amongst whom are $A, B$ and $C$ to speak at a function. The number of ways in which it can be done if $A$ wants to speak before $B$ and $B$ wants to speak before $C$ is
Ten persons, amongst whom are $A, B$ and $C$ to speak at a function. The number of ways in which it can be done if $A$ wants to speak before $B$ and $B$ wants to speak before $C$ is
- A
$\frac{{10\;!}}{6}$
- B
$3\;!\;7\;!$
- C
$^{10}{P_3}\;.\;7\;!$
- D
None of these
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