a) 315 ✖55 + 315✖45 b) 678✖125-25✖678
= 315✖(55+45) =678✖(125-25)
=315 ✖ 100 =678✖100
=31500 =67800
315 x 55 + 315 x 45
= 315 x ( 55 + 45 )
= 315 x 100
= 31500
315 x 55 + 315 x 45
= ( 55 + 45 ) x 315
= 100 x 315
= 31 500
678 x 125 - 25 x 678
= ( 125 - 25 ) x 678
= 100 x 678
= 67 800