Question

1,9,36,100,225,?
? is

Answer 1

the seqence is: (1)square = 1
(1 + 2 )square = 9
( 3+ 3 ) square = 36
( 6+ 4) square = 100
( 10 + 5) square = 225

similarly now , (15 + 6) square
= 441
so the ? is 441

hope it helps