2155 - ( 174 + 2155) + (-68 + 174)
2155 -(174+2155)+(-68+174)
giúp mik nha
2155 -(174+2155)+(-68+174)=2155 -174-2155+(-68)+174
=(2155-2155)+(-174+174)+-68
=-68
Cái này... thật sự có thể tính nhẩm đc mà! Vs lại có phải hơi... dễ không? 😓
2155-(174+2155)+(-68+174)
=2155-174-2155-68+174
=(2155-2155)+(-174+174)-68
=0+0-68
=-68
Tinh nhanh : 2155- (174 + 2155) + (- 68 +174)
2155- (174 + 2155) + (- 68 +174)
=2155-174-2155-68+174
=(2155-2155)+(-174+174)-68
=0+0-68
=-68
= 2155 - 174 - 2155 - 68 +174
= ( 2155 - 2155) + ( -174 + 174) - 68
= 0+ 0 - 68
= -68
2155 - (174 + 2155) + (-68 + 174)
= 2155 - 174 - 2155 - 68 +174
= -68
Tính hợp lý:2155-(174+2155)+(-68+174)
2155.......?=68
\(2155-\left(174+2155\right)+\left(-68+174\right)\)
= \(2155-174-2155-68+174\)
\(=\left(-68\right)\)
Tính hợp lý
2155-(174+2155)+(-68+174)
ta phải bỏ giấu (,) đi:
suy ra: =2155-174-2155-68+174
=(2155-2155)-(-174+174)-68
=0-0-68
=-68
2155-(174+2155)+(-68+174)=2155-174-2155-68+174=(2155-2155)+(-174+174)-68=0+0-68=-68
1, 2155 - (174 + 2155 ) + ( -68 + 174 )
2, -25 . 72 + 25 . 21 - 49 . 25
1, 2155 -(174 + 2155) + (-68 + 174)
=2155 - 174 - 2155 -168 + 174
=(2155-2155)+(-174+174)-168
=-168
2, -25.72 + 25.21-49.25
=25.-72+25.21-49.25(vi -25.72=25.-72)
=25(-72+21-49)
=25.(-2)
=-50
Tính bằng cách hợp lí:
a) 512. (2 - 128) - 128.(-512)
b) 2155 - (174 + 2155) + (-68 + 174)
a) \(512.\left(2-128\right)-128.\left(-512\right)\)
\(=512.\left(-126\right)-128.\left(-512\right)\)
\(=\left(-512\right).126-128.\left(-512\right)\)
\(=\left(-512\right)\left(126-128\right)\)
\(=\left(-512\right).\left(-2\right)\)
\(=1024\)
b) \(2155-\left(174+2155\right)+\left(-68+174\right)\)
\(=2155-174-2155-68+174\)
\(=2155-2155-174+174-68\)
\(=-68\)
NĂM MỚI AN LÀNH
Ta có :
\(a)\)\(512.\left(2-128\right)-128.\left(-512\right)\)
\(=\)\(512\left(2-128+128\right)\)
\(=\)\(512.2\)
\(=\)\(1024\)
a) \(512.\left(2-128\right)-128.\left(-512\right)\)
\(=512.2-512.128+128.512\)
\(=1024\)
b) \(2155-\left(174+2155\right)+\left(-68+174\right)\)
\(=2155-174-2155-68+174\)
\(=-68\)
Tinh mot cach hop li nhat :
a) 512.(2-128) - 128.(-512)
b) 2155-(174 + 2155) + ( -68 + 174)
a, =512 . -126 - 128 . -512
= -512 . 126 - 128 . -512
= -512.[126 - 128]
= -512.-2
=1024
b, =2155 - 174 - 2155 + 106
=2155-2155 - 174 +106
=0 - 174 +106
=-68
a) \(=512\cdot\left(2-128\right)+128\cdot512 \)
\(=512\cdot\left(2-128+128\right)\)
\(=512\cdot2=1024\)
2155 - (174 + 2155) + ( -68 + 174)
= ( 2155 - 2155 ) + ( 174 - 174 ) + ( -68 )
= 0 + 0 + ( -68 )
= -68
tính cách hợp lí
512 .( 2-128) -128 . (-512)
2155 - (174 + 2155) + (-68 + 174)
giúp lần 2
Tính hợp lí nhất
1, 2155– (174 + 2155) + (-68 + 174) 2, -25 . 72 + 25 . 21 – 49 . 25 3, 35(14 –23) – 23(14–35) 4, 8154– (674 + 8154) + (–98 + 674) 5, – 25 . 21 + 25 . 72 + 49 . 25 6, 27(13 – 16) – 16(13 – 27)
|
7, –1911 – (1234 – 1911) 8, 156.72 + 28.156 9, 32.( -39) + 16.( –22) 10, –1945 – ( 567– 1945) 11, 184.33 + 67.184 12, 44.( –36) + 22.( –28)
|
1) \( 2155 – (174 + 2155) + (-68 + 174) = -68\) 2) \(-25 . 72 + 25 . 21 – 49 . 25=-2500\) 3) \(35.(14 –23) – 23.(14–35)=168\) 4) \(8154 – (674 + 8154) + (–98 + 674)=-98\) 5) \(25.21+25.72+49.25=2399\) 6) \(27.(13-16)-16.(13-27)=143\) 7) \(–1911 – (1234 – 1911) =-1234\) |