a) | - 25 | + ( 45 - 126 + 174) - (174 + 145 - 126)
b) 25.22 - ( 9-14) + ( 29 - 34 + 20 )
Tính nhanh: 126 + 82 - 26 + 174 - 80 - 104 =
Tính nhanh (0,5 điểm)
126 + 82 - 26 + 174 - 80 - 104 = (126 - 26) + (82 - 80) + (174 - 104)
= 100 + 2 + 70
= 172
Câu 1: Tính
a, ( -14 ) + 5 + 17 + 14
b, 40 + 13 + ( -25 ) + ( -13 )
c, ( -5 ) + ( -146 ) + ( -15 ) + 14
d, ( -2 ) + ( -5 ) + 20 + ( -13 )
Câu 2: Tính
a, ( 123 - 37 ) - 123
b, ( -224 ) - ( 34 - 224 )
c, 126 - ( 126 - 33 )
d, ( -53 23 ) - ( 567 - 53 )
Câu 1:
a:=17+5=22
b: =40-25=15
Thực hiện phép tính:
1. 68 + 32 + 18;
2. 315 + 172 − 72 + 75;
3. 84 + 325 + (116 − 325) − (−40);
4. 214 + (−54) + (−14) + (−46);
5. 8.25.29.22.125;
6. 12.141 − 12.41;
7. 25.154 − 25 + 47.25;
8. 25.(215 + 170) + 170.25 + 215.175;
9. [530 + 4.(12 − 7)30] : 529;
10. 245 − [(32 − 22).10 − 5];
11. 25.23 − (9 − 14) + (29 − 34 + 20);
12. 25+(45−126+174)−(174+145−126);
13. 27 : {480 : [400 − (120 + 24.5)]};
14. 17+(−20)+(23+9−26)+...+53+(−56).
Tìm số nguyên x, biết:
1. x − 12 = 5;
2. x − (−15) = −2005;
3. 28 − x = 29 + (−11);
4. 250 : (x − 8) = 25;
5. 400 − 2(x + 25) = 100;
6. 3x + 7 = 22.10;
7. 2x + 3 = 54 : 52;
8. 18 + 3(x − 2) = 8.(23 − 5);
lm đc nhưng hơi lâu, bn cs chờ đc ko?
nhiều quá nên ko làm đâu
em gửi ít thôi mới làm được
Bài 1: Tính một cách hợp lý
1/ 2155 - (174 + 2155) + (-68 + 174)
2/ -25 . 72 + 25 . 21 - 49 . 25
3/ 35 (14 - 23) - 23 (14-45)
4/ 8154 - (674 + 8154) + (-98 + 674)
5/ - 25 . 21 + 25 . 72 + 49 . 25
1/ 2155-(174+2155)+(-68+174)
=2155-174-2155-68+174
=[2155+(-2155)]+[(-174)+174]+(-68)
=0+0+(-68)
=-68
2/ -25.72+25.21-49.25
=25.(-72)+25.21-49.25
=25.[(-72)+21+(-49)]
=25.(-100)
=-2500
3/ 35.(14-23)-23.(14-45)
=35.14-35.23-23.14-23.45
=(35.14-23.14)+(-35.23-23.45)
=(35.14-23.14)+(-35.23-45.23)
=14.(35-23)+23.(-35-45)
=14.12+23.(-80)
=168+(-1840)
=-1672
4/ 8154-(674+8154)+(-98+674)
=8154-674-8154-98+674
=[8154+(-8154)]+[(-674)+674]+(-98)
=0+0+(-98)
=-98
5/ -25.21+25.72+49.25
=-12.25+25.72+49.25
=25.(-12+72+49)
=25.109
=2725
Đúng thì chọn đúng cho mình nhé !
27(13-16)-16(13-27)
Thực hiện phép tính ( tính nhanh nếu có thể)
a) (2345 + 45) - 2345 b) (-2010) - (119 - 2010)
c) (18 + 29) + (158 - 18 - 29) d) 126 + (-20) + 2004 + (-106)
e) (-199) + (-200) + (201) f) 99 + (-100) + 101
g) 217 + [ 43 + (-217) + (-23)]
a: \(\left(2345+45\right)-2345\)
\(=2345+45-2345\)
\(=45+\left(2345-2345\right)\)
=45+0
=45
b: \(\left(-2010\right)-\left(119-2010\right)\)
\(=-2010-119+2010\)
\(=\left(-2010+2010\right)-119\)
=0-119
=-119
c: \(\left(18+29\right)+\left(158-18-29\right)\)
\(=18+29+158-18-29\)
\(=158+\left(18-18\right)+\left(29-29\right)\)
=158+0+0
=158
d: \(126+\left(-20\right)+2004+\left(-106\right)\)
\(=126-20+2004-106\)
\(=\left(126-20-106\right)+2004\)
=0+2004
=2004
e: \(\left(-199\right)+\left(-200\right)+\left(201\right)\)
\(=-199-200+201\)
\(=-199+\left(201-200\right)\)
=-199+1
=-198
f: \(99+\left(-100\right)+101\)
\(=\left(99+101\right)-100\)
=200-100
=100
g: \(217+\left[43+\left(-217\right)+\left(-23\right)\right]\)
\(=217+43-217-23\)
\(=\left(217-217\right)+\left(43-23\right)\)
=0+20
=20
1 . Tính hợp lí
a) (-37)+14+26+37
b) (-24)+6+10+24
c) 15+23+9-25)+(-33)
d) 60+33+(-50)+(-33)
e) (-16)+(-209)+(-14)+209
g) (-12)+(-13)+36+(-11)
h) -16+24+16-34
r) 25+37-48-25-37
u) 2575+37-2576-29
i) 34+35+36+37-14-15-16-17
2 . Bỏ ngoặc rồi tính
a)-7264+(1543+7264)
b) (144-97)-144
c) (-145)-(18-145)
d) 11+(-11+27)
e) (27+514)-(486-73)
g) (36+79)+(145-79-66)
h) 10-[12-(-9-1)
r) (-28-29+43)-(43+38)
u ) 271 - [(-43)+271-(-17)]
i ) -144-[29-(+144)-(+144)
a) (-37)+14+26+37 = ( -37 + 37) + ( 14 + 26) = 40
b) (-24)+6+10+24 = ( - 24 + 24) + ( 6 + 10) = 16
c) 15+23+9-25)+(-33) = (15 - 25) + ( 23 - 33) + 9
= - 10 - 10 + 9
= - 11
d) 60+33+(-50)+(-33) = ( 60 -50) + ( 33 - 33)
= 10
e) (-16)+(-209)+(-14)+209 = ( - 16 - 14) + ( - 209 + 209)
= - 30
g) (-12)+(-13)+36+(-11)= ( - 11 -12 - 13 ) + 36
= - 36 + 36 = 0
h) -16+24+16-34 = ( - 16 + 16)+(24 - 34) = - 10
r) 25+37-48-25-37 = (25 - 25)+(37 - 37) - 48 = - 48
u) 2575+37-2576-29 = ( 2575 - 2576) + ( 37 - 29)
= - 1 + 8 = 7
i) 34+35+36+37-14-15-16-17 = ( 34 - 14 )+(35 - 15)+(36-16)+ (37 - 17)
= 80
2 . Bỏ ngoặc rồi tính
a)-7264+(1543+7264) = - 7264 + 1543 + 7264
= 1543
b) (144-97)-144 = 144 - 97 - 144 = - 97
c) (-145)-(18-145) = - 145 - 18 + 145 = - 18
d) 11+(-11+27) = 11 - 11 + 27 = 27
e) (27+514)-(486-73) = 27 + 514 - 486 + 73
= 128
g) (36+79)+(145-79-66) = 36 + 79 + 145 - 79 - 66
= 115
h) 10-[12-(-9-1) = 10 - ( 12 + 9 + 1)
= 10 - 22
= - 12
r) (-28-29+43)-(43+38) = - 28 - 29 + 43 - 43 - 38
= - 95
u ) 271 - [(-43)+271-(-17)] = 271 + 43 - 271 - 17 = 26
i ) -144-[29-(+144)-(+144) = - 144 - 29 - 144 + 144 = -173
Bỏ ngoặc rồi tính:
c, 126 - (126 - 33)=
d, (-53 - 23) - (567 - 53) =
e, 145 - (23 - 45) - (-23 - 10) =
c, 126 - (126 - 33)=126-126+33=33
d, (-53 - 23) - (567 - 53) =-76-567+53=-590
e, 145 - (23 - 45) - (-23 - 10) =145+22+33=200
126 - ( 126 -33) = 126 -126 + 33 = 33
(-53-23)-(567-53)= -76 -567 + 53 = -590
145 - ( 23 -45) -( -23 -10) = 145 -23 + 45 +23 + 10= 200
c)= 126 - 126 + 33= 33
d) = -53 - 23 - 567 + 53 = (-53 + 53) - (23 + 567) =0 - 590 = -590
e)= 145 - 23 + 45 + 23 + 10= 145 + (-23 + 23 ) + (45 + 10)= 145 + 0+55= 145 + 55 =200
Thực hiện phép tính:
A.(2345 - 45 ) + 2345
B.(-2010)-(119 - 2010)
C (18+29)+(158-18-29)
D 126+ (-20) + 2004 +(-106)
E (-199) + (-200) + (-201)
G 217 + <43 + (-217) + (-23) >
<> Dấu này là ngoặc vuông ak
a) (2345-45)+2345
= 2300 + 2345
= 4645
b) (-2010)-(119-2010)
= -2010-119+2010
= (2010-2010)-199
= -199
c) (18+29)+(158-18-29)
= 18+29+158-18-29
= (18-18)+(29-29)+158
= 158
d) 126+(-20)+2004+(-106)
= 126 -20 + 2004 - 106
= (126-20-106) +2004
= 2004
e) (-199)+(-200)+(-201)
= -(199+200+201)
= -600
g) 217+ [43+(-217)+(-23)]
= 217+ 43 - 217 + 23
= (217-217)+(43-23)
= 20
-Học tốt-
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) \(–1911 – (1234 – 1911) =-1234\) |