What is the next number of the following sequence - 54, 21, 3, 9, 81, ??

Question

Find the number that comes next in the following series:

3, 7, 12, 14, 16, 19, 21, 25, 30, 41, 45, 52, 54, 56, 59, 61, 65, 70, ?

Answer 1

In 54, the second digit is 4, and the first digit is 5.
Therefore, 4²+5
=16+5
=21
Similarly, 1²+2
=1+2
=3
Similarly, 3²+0
=9+0
=9
Similarly, 9²+0
=81+0
=81
Similarly, 1²+8
=1+8
=9
Thus, you will get the answer as 9.

Answer 2

first num is -54. adding the digits gives 9 whch is the 4th num. 2nd num is 21, adding the digits gives 3 whch is the 3rd num. now, following the same order frm the left side(-54,21,3, 9,81,12) as shown the gap, adding the first num i.e. 21 (frm left syd) gives 3 whch is the 4th num(frm left syd). adding the 2nd num(frm lft syd) i.e. 81 gives 9 whch is the 3rd num(frm left syd)