question_answer

Direction: What will come in place of the question mark (?) in the following number series?

?           17         29         59         115       205

A)  14                               

B)  16          

C)  15                               

D)  13          

E)  11

Correct Answer: C

Solution :

 The series is \[15+1\times 2=17,17+3\times 4=29,29+5\times 6\] \[=59,59+7\times 8=105,105+9\times 10=205,...\]