Bài 4:Bỏ dấu ngoặc rồi tính
a, (3965 - 2378) - (437 -1378) - 528
b, (-457) + (-123) + 23 + 237
c, (-329) - (15 - 101) - (25 - 440)
(1267-196)-(267-204)
(3965-2378)-(437-1378)-528
2002-79+15)-(-79+15)
-329-(15-101)-(25-440)
(1267 - 196) - (267 - 204)
= 1267 - 196 - 267 + 204
= (1267 - 267) + (204 - 196)
= 1000 + 8
= 1008
(3965 - 2378) - (437 - 1378) - 528
= 3965 - 2378 - 437 + 1378 - 528
= 3965 - (437 + 528) - (2378 - 1378)
= 3965 - 965 - 1000
= 3000 - 1000
= 2000
2002 - 79 + 15 - (-79) - 15
= 2002 - (79 - 79) + (15 - 15)
= 2002 - 0 + 0
= 2002
-329 - (15 - 101) - (25 - 440)
= - 329 - 15 + 101 - 25 + 440
= (440 + 101 - 329) - (15 + 25)
= (541 - 329) - 40
= 212 - 40
= 172
Bài 1 Bỏ ngoặc rồi tính
b) (3965-2378-2378)-(437-1378)-528
Lời giải:
$=3965-2378-2378-437+1378-528$
$=3965-(2378-1378)-2378-437-528$
$=3965-1000-2378-437-528$
$=2965-(2378+437+528)=2965-3343=-378$
Bỏ dấu ngoặc rồi tính:
-329 - (15 - 101) - (25 - 440)
=-329-15+101-25+440
=-344 + 101-25+440
=-243-25+440
=-268+440
=172
-329 -(15-101)-(25-440)
= -329 -15 + 101 -25+440
= 172
(3965-2378)-(437-1378)-528
(3965-2378)-(437-1378)-528
=1587-(-941)-528
=1587+941-528
=2528-528
=2000
Tính nhanh(nhớ bỏ dấu ngoặc)
a)1000-(137+572)+(263-291)
b)-329+(15-101)-(25-440)
a. 1000 - (137 + 572) + (263 - 291)
= 1000 - 137 - 572 + 263 - 291
= 1000 - (137 + 572 + 291) + 263
= 1000 - 1000 + 263
= 263
b. -329 + (15 - 101) - (25 - 440)
= -329 + 15 - 101 - 25 + 440
= (15 + 440) - (329 + 101 + 25)
= 455 - 455
= 0
a) 1000 - 137 - 572 + 263 - 291
= 1000 - ( 137 + 572 + 291 ) + 263
= 1000 - 1000 + 263
= 263
b) -329 + 15 - 101 - 25 + 440
= ( -329 + 15 - 101 - 25 ) + 440
= -440 + 440
= 0
a)1000-(137+572)+(263-291)
=1000-137-572+263-291
=263
b)-329+(15-101)-(25-440)
=-329+15-101-25+440
=0
Tính nhanh
a (3965-2378)-(437-1378)-528
b-(2003+80-91)-(515-80+91)
Tính nhanh
(3965-2378)-(437-1378)-528
Tính
(-x+31)-39=-69+11
(3965-2378)-(437-1378)-528
=3965-2378-437-1378-528
=(3965-(437+528))-(2378-1378)
=3000-1000
=2000
Bài 1 :
\((3965-2378)-(437-1378)-528\)
\(=3965-2378-437+1378-528\)
\(=3965-(2378-1378)-(437+528)\)
\(=3965-1000-965\)
\(=(3965-965)-1000\)
\(=3000-1000\)
\(=2000\)
Bài 2 :
\((-x+31)-39=-69+11\)
\((-x+31)-39=-58\)
\(-x+31=-58+39\)
\(-x+31=-19\)
\(-x=-19-31\)
\(-x=-50\)
\(=>x=50\)
(-x+31)-39=-69+11
(-x+31)-39=-58
-x+31 =-58+39
-x+31 =-19
-x =-19-31
-x =-50
Tính nhanh :
a) ( 1267 - 196 ) - ( 267 + 304 )
b) ( 3965 - 2378 ) - ( 437 - 1378 ) - 528
a) ( 1267-196 ) - ( 267 + 304 )
= ( 1267 - 267 ) - ( 196 + 304 )
= 1000 - 400
= 600
b ) ( 3965 - 2378 ) - ( 437-1378 ) - 528
=
a, (1267-196)-(267+304)
=(1267-267)-(196+304)
=1000-500
=500
b; (3965-2378)-(437-1378)-528
=(3965-528-437)-(2378-1378)
=3000-1000
=2000