Bài 1 .Tính nhanh:
1.5-197-2015-2015
2.-45789-357-45789+57
3.1259-1409-12+1259+1409
4.2750-1229+2750-[-438-29-438]
5.173-536+173-[29-29+526]
6.-[-171+171+223]-[172-105+172]+223
Giúp mk với!
Mk cần gấp!
Bài 1 .Tính nhanh:
1.5-197-2015-2015
2.-45789-357-45789+57
3.1259-1409-12+1259+1409
4.2750-1229+2750-[-438-29-438]
5.173-536+173-[29-29+526]
6.-[-171+171+223]-[172-105+172]+223
Giúp mk với!
Mk cần gấp!
Đáp án:
$↓↓$
Giải thích các bước giải:
$1)5 – 197 – 2015 – 2015$
$= ( 5 – 197) – ( 2015 + 2015)$
$= – 192 – 4030$
$= – ( 192 + 4030)$
$= -4222 $
$______________________________$
$2)-45789 – 357 – 45789 + 57$
$= (45789 – (-45789)) + (57 – 357)$
$= 91578 + (-300)$
$= 91578 – 300$
$= 91278$
$______________________________$
$3)1259- 1409- 12+ 1259+ 1409$
$=1259-12+1259$
$=2518-12$
$=2506 $
$______________________________$
$4)2750- 1229+ 2750-[- 438- 29- 438 ]$
$=2750 – 1229 + 2750 + 438 + 29 + 438$
$=(2750 + 2750) + ( 438 + 438 ) + ( 29 – 1229 )$
$= 5500 + 876 + ( -1200 )$
$= 6376 – 1200$
$= 5176 $
$______________________________$
$5)173- 536 +173-[ 29- 29+ 526]$
$= 173- 536 +173- 526$
$= (173 + 173) – 536 – 526$
$= 346 – 536 – 526$
$= -716 $
$______________________________$
$6)-[-171+ 171+ 223]-[ 172- 105+ 172]+ 223$
$= 171-171-223-172+105-172+223$
$=(171-171)+(223-223)+(-172-172)+105$
$ =0+0+(-344)+105$
$=-239$
5 – 197 – 2015 – 2015
= ( 5 – 197) – ( 2015 + 2015)
= – 192 – 4030
= – ( 192 + 4030)
= -4222
-45789 – 357 – 45789 + 57
= (45789 – (-45789)) + (57 – 357)
= 91578 + (-300)
= 91578 – 300
= 91278
1259- 1409- 12+ 1259+ 1409
=1259-12+1259
=2518-12
=2506
2750- 1229+ 2750-[- 438- 29- 438 ]
=2750 – 1229 + 2750 + 438 + 29 + 438
=(2750 + 2750) + ( 438 + 438 ) + ( 29 – 1229 )
= 5500 + 876 + ( -1200 )
= 6376 – 1200
= 5176
173- 536 +173-[ 29- 29+ 526]
= 173- 536 +173- 526
= (173 + 173) – 536 – 526
= 346 – 536 – 526
= -716
-[-171+ 171+ 223]-[ 172- 105+ 172]+ 223
= 171-171-223-172+105-172+223
=(171-171)+(223-223)+(-172-172)+105
=0+0+(-344)+105
=-239