Number and Alphabet series

In each of the following questions, a series of number / alphabet is given which follow certain rules. One of the number / alphabet is missing. Choose the missing number / alphabets from the alternatives given below and mark it on your answer - sheet as directed. 18, 24, 21, 27, ?, 30, 27,

In each of the following questions, a series of number / alphabet is given which follow certain rules. One of the number / alphabet is missing. Choose the missing number / alphabets from the alternatives given below and mark it on your answer - sheet as directed. ELFA, GLHA, ILJA, ? , MLNA

Which letter will be midway between 4th letter from the right and 12th letter from the right in the English alphabet series?

What will come in place of the question mark(?) in the following alphabet series based on their positions in the English alphabet? DGH JMN ?VYZ

In the following questions, a series is given with one or more number(s) / alphabet missing. Choose the correct alternative from the given options. BE, DH, ??, HN, JQ

Complete the alphabetical series choosing the most appropriate option given below. U,O,ul?,E,A

What will come in place of the question mark(?) in the following alphabet series ? TG HU VI JW ?