f)-7264+(1543+7264)
=-7264+1543+7264
=(-7264+7264)+1543
=0+1543
=1543
g)(-145)-(18-145)
=-145-18+145
=(-145+145)-18
=0-18
=-18
h)(27+514)-(486-73)
=27+514-486+73
=(27+73)+(514-486)
=100+28
=128
i)10-[12-(-9-1)]
=10-[12+9+1]
=10-12-9-1
=10-(9+1)-12
=10-10-12
=0-12
=-12
j)271-[(-43)+271)-(-17)]
=271-[-43+271+17]
=271+43-271-17
=(271-271)+(43-17)
=0+26
=26
TICK mình nha!!!!