Multiplication of 999 with any number
Multiply the number by 1000 and then subtract the number
from it to get answer
1. 51 x 999 = 51 x(1000-1)
= 51 x 1000-51 = 51000-51 = 50949.
2. 147 x 999 = 147 x (1000-1)
= 147000-147 = 146853.
3. 3825 x x999 = 3825
x (1000-1) = 3825000-3825 = 3821175