Solve mentally.
1,00,000-8999
Given numerical expression is 1,00,000-8999
Replace every zero from the left with 9 and the last zero with a 10
100000|⏟|⏟|⏟|⏟|⏟999910
Now subtract each digit from 9 and last digit from 10
999910-899991001¯
Hence, the value of 1,00,000-8999 is 91001
1,00,000-78,342
5,00,000-7896
10,00,000-7,39,145
100,00,000-72,19,258
200,000-128