Bỏ dấu ngoặc rồi tính :
-7264 + ( 1543 + 7264 )
(144 – 97 ) -144
( -145 ) – ( 18 -145 )
111 + ( -11 + 27 )
( 27+ 514 ) – (486-73)
( 36 + 79 ) + ( 145 – 79 – 36 )
( 38 -29+ 43 ) – ( 43 + 38 )
271 – [ ( -43 ) + 271 – ( -17)]
-144 – [ 29 – ( + 144 ) – ( + 144 ) ]
–7264 + ( 1543 + 7264 )
=-7264+1543+7264
=(-7264+7264)+1543
=0+1543
=1543
(144 – 97 ) -144
=144-97-144
=(144-144)-97
=0-97
=-97
( -145 ) – ( 18 -145 )
=-145-18+145
=(-145+145)-18
=0-18
=-18
111 + ( -11 + 27 )
=111+-11+27
=111-11+27
=100+27
=127
( 27+ 514 ) – (486-73)
=27+514-486+73
=(27+73)+(514-486)
=100+28
=128
( 36 + 79 ) + ( 145 – 79 – 36 )
=36+79+145-79-36
=(36-36)+(79-79)+145
=0+0+145
=145
( 38 -29+ 43 ) – ( 43 + 38 )
=38-29+43-43-38
=(38-38)+(43-43)-29
=0+0-29
=-29
271 – [ ( -43 ) + 271 – ( -17)]
=271-[-43+271+17]
=271+43-271-17
=(271-271)+(43-17)
=0+26
=26
-144 – [ 29 – ( + 144 ) – ( + 144 ) ]
=-144-[29-144-144]
=-144-29+144+144
=(-144+144)+(-29+144)
=0+115
=115
Đáp án:
1/ -7264+(1543+7264)
= -7264+1543+7264
=( -7264+7264) + 1543
= 0+ 1543
= 1543
2/(144-97)-144
= 144-97-144
= (144-144)-97
= 0-97
= -97
3/(-145)-(18-145)
= -145 – 18 +145
= ( -145 + 145) -18
=0-18
= -18
4/111+(-111+27)
= 111 + (-111) +27
= 0+27
=27
5/(27+514)-(486-73)
= 27+514 – 486+73
= (27+73) + ( 514-486)
= 100 + 28
=128
6/(36+79)+145-79-36)
= 36+79 + 145 – 79-36
= (36-36) + ( 79-79) + 145
= 0+0+145
=145
7/10-[12-(-9-1)]
= 10-( 12 + 9 + 1)
= 10- 22
= -12
8/(38-29+43)-(43+38)
= 38 – 29 +43 – 43 – 38
= (38-38)+ ( 43-43) -29
=0+0-29
=-29
9/271-[(-43)+271-(-17)]
= 271- (-43 +271 + 17)
= 271 + 43 – 271 -17
= (271-271) + ( 43 – 17)
= 0+ 26
=26
10/-144-[29-(+144)-(+144)]
= -144 – (29 – 144- 144)
= -144 – 29 +144+144
= ( -144 +144)+ ( 144-29)
= 0 + 115
=115
CHÚC BẠN HỌC TỐT!!