198 x 209 + 99 x 1582
= 99 x 2 x 209 + 99 x 1582
= 99 x 418 + 99 x 1582
= 99 x ( 418 + 1582 )
= 99 x 2000
= 198000
198 x 209 + 99 x 1582
= 99 x 2 x 209 + 99 x 1582
= 99 x 418 + 99 x 1528
= 99 x ( 418 + 1582 )
= 99 x 2000
= 198000
\(=198x209+99x2x791=198x209+198x791=198x\left(209+791\right)\)
\(=198x1000=198000\)