(175+5mủ2+13)-[-15+175-(-25)]
(175+25+13)-(-15+175+25)
= 175 + 25 + 13 +15 - 175 - 25
= 13 + 15
= 28
hok tốt!
(175+25+13)-(-15+175+25)
=175+25+13+15-175-25
=175-175+25-25+13+15
=0+0+28
=28
HOK TỐT
( 175 + 25 + 13 ) - ( - 15 + 175 + 25 )
= 213 - 185
= 28
) (123 – 27) + (27 + 13 – 123)
b) (175 + 25 + 13) – [(-15) + 175 + 25]
c) (2012 – 119 + 29) – [(-119) + 29]
d) – (55 – 80 + 91) – (2012 + 80 – 91)
mn giúp mình với mình đang gấp
c: =2012-119+29+119-29
=2012
Thực hiện phép tính :
a) 123 - 27 + 27 + 13 - 123
b) 175 + 25 + 13 + 15 - 175 - 25
c) 53 x 39 + 47 x 39 + 53 x 21 + 47 x 21
d) 49 x 35 + 49 x 16 - 49 x 61
a) `123 - 27 + 27 + 13 - 123`
`= (123 - 123) + (27 - 27) + 13`
`= 0 + 0 + 13`
`= 13`
`---`
b) `175 + 25 + 13 + 15 - 175 - 25`
`= (175-175)+(25-25)+25+13`
`=0+0+25+13`
`=28`
`---`
c) \(53\times39+47\times39+53\times21+47\times21\)
\(=\text{[}\left(53+47\right)\times39]+\left[\left(53+47\right)\times21\right]\)
\(=\left(100\times39\right)+\left(100\times21\right)\)
\(=3900+2100\)
`=6000`
`---`
d) \(49\times35+49\times16-49\times61\)
`=` \(49\times\left(35+16-61\right)\)
`=` \(49\times\left(-10\right)\)
`=-490`
Bỏ dấu ngoặc rồi tính:
a) (123 - 27)+ (27+ 13-123); b) (175 + 25 + 13)-(-15 + 175 + 25);
c) (2012 - 119 + 29) - (-119 + 29); d) -(55 - 80 + 91) - (2012 + 80 - 91).
e) 123 + [54 + (-123) + 46]; f) - 64 + [(-110 + 64 + 71].
Bỏ dấu ngoặc rồi tính:
a) (123 - 27)+ (27+ 13-123) -= 123 - 27 + 27 + 13 - 123 = 13
b) (175 + 25 + 13)-(-15 + 175 + 25) = 175 + 25 + 13 + 15 - 175 - 25 = 28
c) (2012 - 119 + 29) - (-119 + 29) = 2012 - 119 + 29 + 119 - 29 = 20122
d) -(55 - 80 + 91) - (2012 + 80 - 91) = - 55 + 80 - 91 - 2012 - 80 + 91 = - 2067
e) 123 + [54 + (-123) + 46] = 123 + 54 - 123 + 46 = 100
f) - 64 + [(-110 + 64 + 71] = -64 -110 +64 + 71 = -39
1) 31-3 ( x+2 ) = 7
2) 175-25 ( 2x - 1 ) = 175
3) 25 - x/2 = 19
4) 2 ( x-1 ) + 3 = 15
1) 31-3.(x+2) = 7
3.(x+2) = 31- 7
3.(x+2) = 24
x+2 = 24:3
x + 2 = 8
x = 8-2
x = 6
2) 175-25.(2x-1) = 175
25.(2x-1) = 175- 175 = 0
2x-1 = 0 : 25 = 0
2x = 0 + 1 = 1
x = 1 : 2 = 0,5
3) 25 - x/2 = 19
x/2 = 25-19
x/2 = 6
x : 2 = 6
x = 6 x 2 = 12
4) 2.(x-1)+3 = 15
2.(x-1) = 15 - 3 = 12
x - 1 = 12 : 2 = 6
x = 6+1 = 7
So sánh
a)17/20 và 18/19 b)19/18 và 2023/2022
c)13/17 và 135/175 d)53/63 và 535/636
e)13/15 và 22/25 \(\dfrac{2023}{2023^2+1}và\dfrac{2022}{2022^2+1}\)
a) \(\dfrac{17}{20}< \dfrac{18}{20}< \dfrac{18}{19}\Rightarrow\dfrac{17}{20}< \dfrac{18}{19}\)
b) \(\dfrac{19}{18}>\dfrac{19+2024}{18+2024}=\dfrac{2023}{2022}\Rightarrow\dfrac{19}{18}>\dfrac{2023}{2022}\)
c) \(\dfrac{135}{175}=\dfrac{27}{35}\)
\(\dfrac{13}{17}=\dfrac{26}{34}< \dfrac{26+1}{34+1}=\dfrac{27}{35}\)
\(\Rightarrow\dfrac{13}{17}< \dfrac{135}{175}\)
15^2 - ( 175+(2^3. 5^2 - 6. 25. 2019^0
THU GỌN BIỂU THỨC
a) - ( 4 - x ) + ( 15 - 25 )
b)( a+ 175 ) - ( 175 - 53 ) - ( 53 - 157 )
c)( x -127 ) - ( 123 - x )+ ( - 250 )
d)( x-2 ) - ( 5 -x ) + ( 7 - x )
a) - ( 4 - x ) + ( 15 - 25 )
= - 4 + x + 15 - 25
= - 14 + x
X + 56 x 2 - [ 32+16 x3 : 6-15 ] = 0
420 +65 x 4 =[ X +175 ] : 5 +30
X - 4867 = [ 175 x 2050 x 70 ] : 25 +23
2436 : x =12