Directions (Set of 3 questions): In each of the following questions, a number series is given. After the series, below it, a number along with (A), (B), (C), (D) and (E) is given. You have to complete the series following the same sequence as that of the given series. Then answer the question that follows.
7.4, 9.2, 11.4, 14, 17, 20.4, 24.2
20.4, 21, (A), (B), (C), (D), (E)
Which of the following will come in place of (D)?