Select the missing term from the following number series ?

Answer & Explanation

Option: [C]

The missing term is 20

7 x 0.5 + 0.5 = 4

4 x 1 + 1 = 5

5 x 1.5 + 1.5 = 9

9 x 2 + 2 = 20

20 x 2.5 + 2.5 = 52.5

52.5 x 3 + 3 = 160.5