a) (125 - 679 + 145) - (125 - 679)
= 125 - 679 + 145 - 125 + 679
= ( 125 - 125) - (679 - 679) + 145
= 0 - 0 + 145
= 145
a, (125 - 679 + 145) - (125 - 679)
125-679+145-125+679
=(125-125)+(-679+679)+145
=0+0+145
=145
b, -37 + 54 + (-70) + (-163) + 246
=[-37+(-70)+(-163)]+(54+246)
=[-107+(-163)]+300
=-270+300
=30
Trả lời:
\(a,\)\(\left(125-679+145\right)-\left(125-679\right)\)
\(=125-679+145-125+679\)
\(=\left(125-125\right)-\left(679-679\right)+145\)
\(=0-0+145\)
\(=145\)
\(b,\)\(-37+54+\left(-70\right)+\left(-163\right)+246\)
\(=\left(-37-163\right)+\left(54+246\right)-70\)
\(=-200+300-70\)
\(=100-70\)
\(=30\)
Hok tốt!
Vuong Dong Yet