1382 - 400 = 982
400 - 125 = 275
400 - 190 = 210
400 - 398 = 2
-30 - (-24) = -30 + 24 = -6
The question above would be written as 950--400 and when you have a minus and a minus together they make a positive, so the actual question is 950+400 which equals 1350.
841 minus 441 is 400.
2,013 minus 30 is 1,983.
30 minus 11 is 19.
4 minus 30 is -26.
-30 minus -6 is -24
30% of 400 = 30% * 400 = 0.3 * 400 = 120