Question

21,29,38,48,59,?complete the following series 14,

Answer 1

Final Answer : 71

Series : 21,29, 38,48,59,?

We observe that,
1)
$29 - 21 = 8 \\ 38 - 29 = 9 \\ 48 - 38 = 10 \\ 59 - 48 = 11$
2) Here, Next Difference is 12 .
Therefore,
? - 59= 12
=> ? = 59+12=71
Therfore, 71 replaces the question mark.