A) (47+53)x298=29800
B) (426+574)x617=617000
C) 396x(37-27)=3960
Trl :
a ) 47 x 298 + 53 x 298
= 298 x ( 47 + 53 )
= 298 x 100
= 29 800
b) 426 x 617 + 617 x 574
= 617 x ( 426 + 574 )
= 610 x 100
= 61 000
c) 396 x 37 - 396 - 17
= 396 ( 37 - 17 )
= 396 x 20
= 7920