The number of words (with or without meaning) that can be formed from all the letters of the word “LETTER” in which vowels never come together is...
Ans : 120
Consonants are L, T, T, R
Vowels are E,E,
Total number of words (with or without meaning) from letters of word 'LETTER' =
Total number of words (with or without meaning) from letters of word 'LETTER' if vowels are together =
Consider the data on x taking the values 0, 2, 4, 8, ...., 2n with frequencies nC0, nC1, nC2,..., nCn respectively. If the mean of this data is , then n is equal to....