Evaluate: _{6} P_{5}

Expression: $_{ 6 } P_{ 5 }$

Use $_{ n } P_{ r }=\frac{ n ! }{ \left( n-r \right) ! }$ to expand the expression

$\frac{ 6 ! }{ \left( 6-5 \right) ! }$

Subtract the numbers

$\frac{ 6 ! }{ 1 ! }$

Calculate the factorial

$\frac{ 6 ! }{ 1 }$

Any expression divided by $1$ remains the same

$6 !$

Calculate the factorial

$720$