Answer:
So, the first solution is a calculator but sometime we don't have a calculator so, do
200 X 300 = A
40 X 90 = B
9 X 8 = C
then add just do multiplication from there like
A + B = D
D + C = E
Then your finally answer would be E
Hope that helps that's the way I do math quick in my head
(Btw the answer to 249 X 398 = 63,672 )