558 - 198 - 135 - 73 = 152
98 over 198 simplified = 49/99
If you mean 198 minus 99 then it is 99
198
987 minus 789 is 198.
The greatest common factor of the numbers 5, 98 and 198 is 1.
It might be possible to work this in your head. Your 98 is 100 minus 2. This means 98 plus 98 is 100 plus 100 minus 2 minus 2. That's 200 minus 4 which gives 196 as the answer.
1/6 x 198 = 33
98/396 = 49/198.
220 - 22 = 198
98 - 69 = 29
7/11 - 6/18 = 126/198 - 66/198 = 60/198 = 10/33