Mathematics - Permutation & Combination Question with Solution | TestHub

 Consonants are $\mathrm{L}, \mathrm{T}, \mathrm{T}, \mathrm{R}$

Vowels are $\mathrm{E}, \mathrm{E},$

Total number of words (without meaning) from letters of word $\text{'}\mathrm{LETTER}\text{'}=\frac{6!}{2!2!}=180$

Total number of words (with or without meaning) from letters of word $\text{'}\mathrm{LETTER}\text{'}$ if vowels are together $=\frac{5!}{2!}=60$

$\therefore$ Required $=180-60=120$