In how many different ways can the letters of the word "DESIGN" be arranged so that the vowels are at the two ends?

Question: In how many different ways can the letters of the word "DESIGN" be arranged so that the vowels are at the two ends?

Solution:
The given word "DESIGN" contains 4 consonants and 2 vowel.
At the two ends the two vowels can be arranged in 2! = 2 ways.
Remaining 4 letters can be arranged in = 4!
= 24

∴ Total number of ways = (24 × 2) = 48