1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 +10= 1111111111

9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888

1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321
11111111 x 11111111 = 123456787654321
111111111 x 111111111=123456789 87654321

12345679 * 9 = 111111111 (9*1)
12345679 * 18 = 222222222 (9*2)
12345679 * 27 = 333333333 (9*3)
12345679 * 36 = 444444444 (9*4)
12345679 * 45 = 555555555 (9*5)
12345679 * 54 = 666666666 (9*6)
12345679 * 63 = 777777777 (9*7)
12345679 * 72 = 888888888 (9*8)
12345679 * 81 = 999999999 (9*9)

9 x 1 = 9 | 9 + 0 = 0
9 x 2 = 18 | 1 + 8 = 9
9 x 3 = 27 | 2 + 7 = 9
9 x 4 = 36 | 3 + 6 = 9
9 x 5 = 45 | 4 + 5 = 9
9 x 6 = 54 | 5 + 4 = 9
9 x 7 = 63 | 6 + 3 = 9
9 x 8 = 72 | 7 + 2 = 9
9 x 9 = 81 | 8 + 1 = 9
9 x 10 = 90 | 9 + 0 = 9

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