0,1,2.9,5.61,9.05,?  Options
A) 11.15 B) 12.15 C) 13.15 D) 14.15 E) 15.15
The series is 0, 1, 2.9, 5.61, 9.05, ...   Fisrt oder differences are 1, 1.9, 2.71, 3.44, ...   Second order differences are 0.9, 0.81, 0.73, ...   Note that the second order differences are powers of 0.9 (0.9, 0.81, 0.729, ...), rounded off to two decimal digits. So next term in second order difference is 0.9^4 = 0.6561 = 0.66. Then, the next term in first order difference is 3.44+0.66 = 4.1. So, the term in the series is 9.05+4.1= 
<gadget id="calculator">9.05+4.1</gadget>
<output>13.15</output>
13.15   ANSWER:13.15
<result>C</result>
0,1,2.9,5.61,9.05,?