Question Number 118822 by Don08q last updated on 20/Oct/20
$$\:\mathrm{In}\:\mathrm{how}\:\mathrm{many}\:\mathrm{ways}\:\mathrm{can}\:\mathrm{the}\:\mathrm{letters}\:\mathrm{of}\: \\ $$$$\:\mathrm{the}\:\mathrm{word}\:{LEVITATE}\:\mathrm{be}\:\mathrm{arranged}\:\mathrm{if} \\ $$$$\:\mathrm{the}\:\mathrm{vowels}\:\mathrm{must}\:\mathrm{not}\:\mathrm{be}\:\mathrm{next}\:\mathrm{to}\:\mathrm{each} \\ $$$$\:\mathrm{other} \\ $$
Answered by benjo_mathlover last updated on 20/Oct/20
$${vowels}\::\:{A},{I},{E}\:,{E} \\ $$$$\Box\blacksquare\Box\blacksquare\Box\blacksquare\Box\blacksquare\Box\:=\:\frac{\mathrm{4}!}{\mathrm{2}!}×\frac{\mathrm{4}!}{\mathrm{2}!}×\begin{pmatrix}{\mathrm{5}}\\{\mathrm{4}}\end{pmatrix}\:=\:\mathrm{144}×\mathrm{5}=\mathrm{720} \\ $$$$\blacksquare={vowels} \\ $$$$\Box={consonant} \\ $$
Answered by mr W last updated on 20/Oct/20
$$\Box\blacksquare\Box\blacksquare\Box\blacksquare\Box\blacksquare \\ $$$$\blacksquare\Box\Box\blacksquare\Box\blacksquare\Box\blacksquare \\ $$$$\blacksquare\Box\blacksquare\Box\Box\blacksquare\Box\blacksquare \\ $$$$\blacksquare\Box\blacksquare\Box\blacksquare\Box\Box\blacksquare \\ $$$$\blacksquare\Box\blacksquare\Box\blacksquare\Box\blacksquare\Box \\ $$$$\Rightarrow\mathrm{5}×\frac{\mathrm{4}!}{\mathrm{2}!}×\frac{\mathrm{4}!}{\mathrm{2}!}=\mathrm{720} \\ $$