So first you do 6×2 since 198 is 2 less than 200
And if you do the math, it would be 12
After that, you do 6×200, since if you round off 198, it would be 209
And if you do the math again, it would be 1200
After that if you subtract 12 from 1200, you would get 1188
So the answer is 1188
( Even if you calculate 6×198the way it is, you would get 1188)
Hope this helps:)