Tính
1+13+23+..........+73
Thực hiện phép tính
1) 23+(-13) +(-50)
2)-5+15+(-123)
3)5871:{928-[(-82)+247)].5
4)40-(4.52-3.23)
5)4)62.5-72+149
6)-210:[16+3.(6+3.22)]+(-2022)
7)5.23+711:79-20230.18
8)400:{5.[360-(290+2.52)]}
9)75-(3.52) -4.53)
1: \(23+\left(-13\right)+\left(-50\right)\)
\(=23-13-50\)
=10-50
=-40
2: \(-5+15+\left(-123\right)\)
\(=\left(-5+15\right)-123\)
=10-123
=-113
3: \(5871:\left\{928-\left[\left(-82+247\right)\right]\right\}\cdot5\)
\(=5871-\left\{928+82-247\right\}\cdot5\)
\(=5871-763\cdot5=5871-3815=2056\)
4: \(40-\left(4\cdot5^2-3\cdot2^3\right)\)
\(=40-4\cdot5^2+3\cdot2^3\)
\(=40-4\cdot25+3\cdot8\)
=40-100+24
=64-100
=-36
5: \(6^2\cdot5-7^2+149\)
\(=36\cdot5-49+149\)
\(=180+149-49\)
=180+100
=280
6: \(-210:\left[16+3\cdot\left(6+3\cdot2^2\right)\right]+\left(-2022\right)\)
\(=-210:\left[16+3\cdot\left(6+3\cdot4\right)\right]+\left(-2022\right)\)
\(=-210:\left[16+3\cdot18\right]+\left(-2022\right)\)
\(=-210:70-2022\)
=-3-2022
=-2025
7: \(5\cdot2^3+7^{11}:7^9-2023^0\cdot1^8\)
\(=5\cdot8+7^2-1\)
=40+49-1
=39+49
=88
8: \(400:\left\{5\cdot\left[360-\left(290+2\cdot5^2\right)\right]\right\}\)
\(=400:\left\{5\cdot\left[360-290-2\cdot25\right]\right\}\)
\(=400:\left\{5\cdot20\right\}\)
\(=\dfrac{400}{100}=4\)
9: \(75-\left(3\cdot5^2\right)-4\cdot5^3\)
\(=75-3\cdot25-4\cdot5^3\)
=-4*125
=-500
tính :
a. l -8 -17 l - l-13
b . (23-49) + ( 13 + 49 )
c . l-13 - 7 l - l-13+7l
d . - (18-73) + ( 18 - 73 + 28 )
a) |-8 - 17| - |-13| = 25 - 13 = 12
b) (23 - 49) + (13 + 49)
= 23 - 49 + 13 + 49
= (23 + 13) + (-49 + 49)
= 36 + 0 = 36
c) |-13 - 7| - |-13 + 7|
= 20 - 6 = 14
d) -(18- 73) + (18 - 73 + 28)
= -18 + 73 + 18 - 73 + 28
= (-18 + 18) + (73 - 73) + 28
= 0 + .0 + 28 = 28
Tính nhanh
C = 4 3 + 3 5 + 7 3 + 2 5 + 1 3
D = 5 12 + 5 3 + 2 12 + 2 3
Bài 1: tính
1, 1-5+7-8+4-1+5-7+8
2, 14-23+(5+14)-(5-23)+17
3, 12-44+9-3+14-19-9-12
4,22-(4-8+12)+(-8-12+4)
1: =1-1+5-5+7-7+8-8=0
2: =14-23+5+14-5+23+17
=28+17=45
3: =12-12+9-9+14-44-3=-33
4: =22-8-8-12+4
=22-16-8
=-2
Bài \(1\)
\(1)\) \(1-5+7-8+4-1+5-7+8\)
\(=(1-1)+(5-5)+(7-7)+(8-8)\)
\(=0+0+0+0\)
\(=0\)
\(2)\) \(14-23+(5+14)-(5-23)+17\)
\(=14-23+5+14-5+23+17\)
\(=(14+14)+(23-23)+(5-5)+17\)
\(=28+17\)
\(=45\)
\(3)\) \(12-44+9-3+14-19-9-12\)
\(=(12-12)+(9-9)+(14-44)+3\)
\(=-30+3\)
\(=-33\)
\(4)\) \(22-(4-8+12)+(-8-12+4)\)
\(=22-4+8-12-8-12+4\)
\(=22+(4+4)+(8-8)+(-12-12)\)
\(=22-24\)
\(=-2\)
tính giá trị biểu thức
a . l -8 - 17 l - l - 13 l
b . ( 23 - 49 ) + ( 13 - 49 )
c . l -56 l - ( 29 + 65 )
d . l - 13 - 7 l - l -13 + 7 l
e . - ( 18 - 73 ) + ( 18 - 73 + 28 )
a ) l - 8 - 17 l - l - 13 l
= l - 25 l + 13
= 25 + 13
= 38
b) ( 23 - 49 ) + ( 13 - 49 )
= - 26 + ( - 36 )
= - 62
l -8 - 17 l - l - 13 l
= |-25| - 13
= 25 - 13
= 12
Bài 1: Thực hiện phép tính
1) 17 . 85 + 15 . 17 – 120
| 9)
|
2) 23 . 17 – 23 . 14 | 10) |
3) 20 + | 11) 5871: {928 -[(-82) +247) ].5} |
4) 28.76+23.28 -28.13 | 12) 112:11-55 |
5) 15.36 – 15.10 + 26.85 | 13) |
6) 75 – ( 3.52 – 4.23) | 14) |
7) 4.52 – 3.23 + 33:32 | 15) |
8) 80 – (4 . 52 – 3 . 23) | 9) 80 – 73.3 10) -8 – 51.2 |
1, 17.( 85+15) -120 = 17. 100 -120 =1700 - 120 =1580
2,
23 . 17 - 23 . 14
= 23(17-14)
=23. 3= 24
Điền dấu >; <; = thích hợp vào ô trống
a ) 3 1 □ 1 3 b ) 10 2 □ 7 3 c ) 8 3 □ 2 7 d ) 1000 2 □ 10 5 e ) 3 1 □ 1 4 f ) 2 3 □ 3 2
Bài 299: Tính
1) 1/3 x 1/2 x 3/7
2) 5/4 x 1/3 + 1/7
3) 8 x ( 8/9-2/3 )
4) 5/6 x 48/20 x 1/2
5) ( 2/5 + 3/4 ) x 8
6) 10 x ( 1/2-1/5 )
Trình bày rõ cách làm giúp nhen!!
1: \(=\dfrac{1}{3}\cdot\dfrac{3}{7}\cdot\dfrac{1}{2}=\dfrac{1}{7\cdot2}=\dfrac{1}{14}\)
2: =5/12+1/7
=35/84+12/84=47/84
3: =8(8/9-6/9)
=8*2/9=16/9
4: \(=\dfrac{5}{12}\cdot\dfrac{12}{5}=1\)
5: =16/5+6
=16/5+30/5=46/5
6: =10*1/2-10*1/5
=5-2=3
a) -24 + 13 + 6 + 24
b ) 28 + ( -6 ) - 50 + 6
c) -27 + ( -789 ) + 9 -73 ) + 789
d) ( -23 ) + ( -17 ) + 50 + ( -10 )
a) -24 + 13 + 6 + 24
= 24 + (-24) + 13 +6
= 0+13+6
= 19
b ) 28 + ( -6 ) - 50 + 6
= 6 + (-6 ) + 28 -50
= 0 +28 - 50
= 28 -50
= -22
a) ( -24 + 24) + 13 + 6 = 19
b) 28 - 50 + ( -6 + 6) = -22
c) ( -27 - 73 ) + (-789 + 789) + 9 = -91
d) {[ -23 + ( -17) ] - 10} + 50 = -50 + 50 = 0