Question

Number of $4$ letter words starting with vowel that can be formed using letters of the word ${}^{\prime }CHEMISTR{Y}^{\prime }$ is

• A. $336$
• B. $504$
• C. $672$
• D. $1008$

Answer 1

The correct option is C $672$

$CHEMISTRY$
The word can be started with either $E$ or $I$.
If the word starts with $E,$ then the rest $3$ letters can be arranged in ${}^8{P}_3=336$ ways.
Similarly, if the word starts with $I,$ then the rest $3$ letters can be arranged in ${}^8{P}_3=336$ ways.
Total words $=2\times 336=672$