do you know when you add 9 or 99 or 999 or 9999 or 99999 like wise
the total always be 9 you know
for example 9 x 2 = 18 .... 1+ 8 = 9
9 x 3 = 27..... 2+ 7 = 9
9 x 4 = 36 ...... 3+ 6 = 9
or you can make a total
for example ... 9 +9 = 18 ..... 1 + 8 = 9
9 + 9 + 9 = 27...... 2+ 7 = 9
like wise you can add any number of 9 the total would be 9 only