What will come in place of question mark (?) in the given number series ?
The difference between the difference of two consecutive terms is in decreasing order of multiples of 3.
85-53 = 32
53-33=20
33-22 = 11
22-17=5
Difference of differences
32-20=12
20-11=9
11-5 - 6
and the next difference must be 3.
5-2=3
Hence the next number must be 2 less than 17 which is 15.
Option E is the correct answer
Create a FREE account and get: