Concept: The question tests on the basics of Counting
Solution:
Number of words where I is not in the 1st or last = Total words - Words where I occupies the 1st and last place
DEFINITION has 10 letters with 3 I's, 2 N's and 1 each of D, E, F, T and O.
Total words = 10! / 3!2!
Words where I comes in the 1st and the last place.
2 I's can be placed in these 2 positions in 1 way. The remaining 8 letters can be arranged in 8!/2! ways (these contain 2 N's)
Therefore Total number of words = 10!3!2!−8!2!=10∗9∗8!6∗2−8!2=8!2(15−1)10!3!2!−8!2!=10∗9∗8!6∗2−8!2=8!2(15−1)
= 40320 * 7 = 282240 (option e)