Find the missing number in the following number series:
22.5, ?, 26.5, 30, 34.5

Given: 22.5, ?, 26.5, 30, 34.5

Logic: Numbers are increasing + 1.5, + 2.5, + 3.5 and + 4.5

22.5 + 1.5 = 24

24 + 2.5 = 26.5

26.5 + 3.5 = 30

30 + 4.5 = 34.5

So, the missing term is 24.

Thus, correct option is (d).