Reason why
"n" x 10 = "n0" for any "n"



5 x 10 = 50, 23 x 10 = 230, etc.

(Case of 1) 1 x 10 = 10

1 x 10 = 1 x (9 + 1)(D1)
= 1 x 9 + 1 x 1(M2)
= 9 x 1 + 1 x 1(M1)
= 9 + 1(M3)
= 10(D1)
(Case of 2) 2 x 10 = 20

2 x 10 = (1 + 1) x 10(S1)
= 1 x 10 + 1 x 10(M2)
= 10 + 10(Case of 1)
= 10 + (9 + 1)(D1)
= (10 + 9) + 1(A1)
= 19 + 1(D2)
= 20(D3)
(Case of 3) 3 x 10 = 30

3 x 10 = (2 + 1) x 10(S1)
= 2 x 10 + 1 x 10(M2)
= 20 + 10(Case of 2)
= 20 + (9 + 1)(D1)
= (20 + 9) + 1(A1)
= 29 + 1(D2)
= 30(D3)
(Case of "n") "n" x 10 = "n0"