4,9,19,34,54,?,109 | series Logical reasoning | WBCS

Complete the series by finding the missing number from the given options.

4,9,19,34,54,?,109

(a) 89
(b) 84
(c) 74
(d) 79

Correct Answer: d

Solution:

4+5=9

9+10=19

19+15=34

34+20=54

54+25=79