a -7 105 -(155 - 7105)+ -355

b 5 - 147 - 2015 - 2015

c 2004 - 15 + 54 - 2004 - 54

d 1 2 5 9-1409 - 12 + 1259 + 1409

e -5 + -37 - 45 + 151 - -37 +151

f -81 - 132 - 547 + 181 - 132 - 53

g 254 - 49 - 75 + 254 - 175 + 549

k+[-171+171+223]-[172-105+172]+223

Đáp án:

Giải thích các bước giải: a) -7105 -(155-7105) + (-135) = -7105 -155+7105-135= (-7105+7105)-(155+135)= 0-290=-290

b) 5-147 -2015 - 2015= 5-(147+2015+2015)=5-(147+4030)=5-4177=-4172

c) 2004 - 15 + 54 -2004-54= (2004 -2004)+(54-54) -15= 0+0-15=-15

d) 1259 -1409 -12 +1259 +1409 = (1259-1259) -(1409-1409)-12=0-0-12=-12