20, 21, 19, 16, 17, 13, 14, 11, ?

Find the next number in the given series.

3, 13, 31, ? , 91

Complete the given number series?
8, 14, 24, 40, ?

A letter series is given below in which some letter are missing. Select the  option that gives the letters that can fill these blanks in that order.
a_ca_bab_ad_abc_db

Select the term that will come in the place of?

7, 11, 19, 31, ?  67

Pick an odd number in the given number series?

4 12 38 87 198

Select the figure that will come next in the following figure series.

380, 645, 557, 656, 762, 875, ?