Here you will learn fastest calculation method:-
EX.:-
15*15 = 225
25*25 = 625
35*35 = 1225
45*45 = 2025
55*55 = 3025
In all calculation first take unit place no. Multyply buy another unit place no.
In first no 15*15 like 5*5 write 25.
Now take tenth place no. Is 1 , add 1 in this no. And multy ply to another tenth place no.
In 15 tenth place no. Is 1 add 1 also now no. Is 2 then 2 multyply by 1 get 2.
Answer is 15*15= 225
25*25=
5*5= 25
2+1=3*2=6 , 25*25 = 625