How many 5 letter words containing 3 vowels and 2 consonants can be
formed using the letters of the word EQUATION so that 3 vowels always
occur together?

Their are 5 vowels from which three can be selected in 5p3 ways and then 2 consonants from 3 can be selcted in 3p2 ways and now the 3 vowels are toghter so they can be intercanged in 3! Ways then the whole 3 entities(3 vowel taken as one and the other two consonants) cen be rearranged in 3! Ways... So total= 5p3 x 3p2 x 3! x 3!= 1080