How many words, with or without meaning, can be formed using all the letters of the word EQUATION at a time so that the vowels and consonants occur together?
Number of letters = (all distinct)
Number of vowels = 5 (e, i, o, u, a)
Number of consonants = 3 (q, t, n)
Step I: Tie the vowels together
Number of permutations =
Step II: Tie the consonants together.
Number of permutations =
Step III: Mix the bundles and any remaining letter to give 1 + 1 + 0 = 2 letters.
Number of permutations =
Hence, the number of permutations, using, fundamental principle of counting
= 120 x 6 x 2 = 1440