Question

Tính hợp lí:

a) -2003+(-21+75+2003)

b) 1152-(374+1152)+(-65+374)

Giúp mk nha !!!

Answer 1

a) -2003+(-21+75+2003)

= -2003-21+75+2003

= (-2003+2003)+(-21+75)

= 0+54

= 54

b) 1152-(374+1152)+(-65+374)

= 1152-374-1152-65-374

= (1152-1152)-(374-374)-65

= 0-0-65

= -65

Answer 2

a) -2003 + (-21+ 75 + 2003)

= -2003 - 21 + 75 + 2003

= [(-2003) + 2003] + [(-21)+ 75]

= 0 + 54= 54

b) 1152- (374+ 1152) + (-65 + 374)

= 1152- 374 - 1152 - 65 + 374

= ( 1152 - 1152) + [(-374) + 374] - 65

= 0 + 0 - 65

= - 65