Out of 7 consonants and 4 vowels, the number of words consisting of 3 consonants and 2 vowels are
Out of 7 consonants and 4 vowels, the number of words consisting of 3 consonants and 2 vowels are
3300
210
120
25200
Solution
We have to choose 3 consonants and 2 vowels from 7 consonants and 4 vowels.
$\therefore$ Number of words $=\left({ }^7 \mathrm{C}_3\right) \times\left({ }^4 \mathrm{C}_2\right) \times 5$ !
$=\frac{7 !}{3 ! 4 !} \times \frac{4 !}{2 ! 2 !} \times 5 !=25200$