3/4 + 5/12 + 13/24 =
Bài 2: Tính hợp lý
1/ (-105). 47 -105. 53; 2/ 45 – 5. (12 + 9)
3/ 24. (16 – 5) – 16. (24 - 5) 4/ 29. (19 – 13) – 19. (29 – 13)
5/ 31. (-18) + 31. ( - 81) – 31 6/ (-12).47 + (-12). 52 + (-12)
Em nến gõ bằng công thức toán học em nhé. Như vậy mọi người nới hiểu đúng đề bài để trợ giúp cho em một cách tốt nhất em ạ!
{-24/11}+{-19/13}+2/11+{-20/13}
-1/12+ -5/6 -4/3
\(-\dfrac{1}{12}+\left(-\dfrac{5}{6}\right)-\dfrac{4}{3}=-\dfrac{1}{12}-\dfrac{5}{6}-\dfrac{4}{3}=-\dfrac{1}{12}-\dfrac{10}{12}-\dfrac{16}{12}=-\dfrac{27}{12}=-\dfrac{9}{4}\)
\(\left(-\dfrac{24}{11}\right)+\left(-\dfrac{19}{13}\right)+\dfrac{2}{11}+\left(-\dfrac{20}{13}\right)=-\dfrac{24}{11}-\dfrac{19}{13}+\dfrac{2}{11}-\dfrac{20}{13}=-\dfrac{24}{11}+\dfrac{2}{11}-\dfrac{19}{13}-\dfrac{20}{13}=-2-3=-5\)
a) x/8 = 3/4 + -5/8
b) x/12 = 3/4 + -2/3
c) 1 + 11/13 = 24/x
d) x/6 - 3/4 = 1/12
`x/8 = 3/4 +(-5/8)`
`=>x/8 = 6/8 +(-5/8)`
`=>x/8 = 1/8`
`=>x=1`
`-----`
`x/12 =3/4 +(-2/3)`
`=>x/12 = 9/12 + (-8/12)`
`=> x/12=1/12`
`=>x=1`
`----`
`1+11/13=24/x`
`=> 13/13 +11/13=24/x`
`=> 24/13 =24/x`
`=>x=13`
`----`
`x/6 -3/4=1/12`
`=>x/6 = 1/12 +3/4`
`=>x/6 = 1/12 + 9/12`
`=>x/6 = 10/12`
`=>x/6= 5/6`
`=>x=5`
\(a)\)
\(\dfrac{x}{8}=\dfrac{3}{4}+\dfrac{-5}{8}\)
\(\Rightarrow\dfrac{x}{8}=\dfrac{1}{8}\)
\(\Rightarrow x.8=1.8\)
\(\Rightarrow x.8=8\)
\(\Rightarrow x=8:8\)
\(\Rightarrow x=1\)
\(b)\)
\(\dfrac{x}{12}=\dfrac{3}{4}+\dfrac{-2}{3}\)
\(\Rightarrow\dfrac{x}{12}=\dfrac{1}{12}\)
\(\Rightarrow x.12=1.12\)
\(\Rightarrow x.12=12\)
\(\Rightarrow x=12:12\)
\(\Rightarrow x=1\)
\(c)\)
\(1+\dfrac{11}{13}=\dfrac{24}{x}\)
\(\Rightarrow\dfrac{24}{13}=\dfrac{24}{x}\)
\(\Rightarrow x.24=24.13\)
\(\Rightarrow x.24=312\)
\(\Rightarrow x=312:24\)
\(\Rightarrow x=13\)
\(d)\)
\(\dfrac{x}{6}-\dfrac{3}{4}=\dfrac{1}{12}\)
\(\Rightarrow\dfrac{x}{6}=\dfrac{1}{12}+\dfrac{3}{4}\)
\(\Rightarrow\dfrac{x}{6}=\dfrac{5}{6}\)
\(\Rightarrow x.6=5.6\)
\(\Rightarrow x.6=30\)
\(\Rightarrow x=30:6\)
\(\Rightarrow x=5\)
Tính hợp lí :
1. 35.18-5.7.28
2/ 45-5.(12+9)
3/ 24.(16-5)-16.(24-5)
4/ 29 . (19--13) -19 . (29-13)
5/ 31. (-18) + 31 . (-81) - 31
6 / ( -12) . 47 + ( -12 ) . 52 + (-12)
7/ 13 .( 23 + 22 ) - 3. ( 17 + 28)
8/ -48 + 48 . ( -78 ) + 48 . (-21)
1) \(35.18-5.7.28=35.18-35.28=35\left(18-28\right)=-350\)
2) \(45-5\left(12+9\right)=45-60-45=-60\)
3) \(24\left(16-5\right)-16\left(24-5\right)=24.16-24.5-16.24+16.5=5\left(16-24\right)=5.8=40\)
4) \(29\left(19-13\right)-19\left(29-13\right)=29.19-29.13-19.29+19.13=13\left(19-29\right)=-130\)
5) \(31.\left(-18\right)+31.\left(-81\right)-31=-31.\left(18+81+1\right)=-3100\)
6) \(\left(-12\right).47+\left(-12\right).52+\left(-12\right)=\left(-12\right)\left(47+52+1\right)=-1200\)
7) \(13\left(23+22\right)-3\left(17+28\right)=13.45-3.45=45.\left(13-3\right)=450\)
8) \(-48+48.\left(-78\right)+48.\left(-21\right)=-48\left(1+78+21\right)=-4800\)
Bài 1: Tính hợp lý
1/ 35.18-5.7.28
2/ 45-5.(12+9)
3/ 24.(16-5)-16.(24-5)
4/ 29.(19-13)-19.(29-13)
5/ 31.(-18)+31.(-81)-31
6/ (-12).47(-12).52+(-12)
7/ 13.(23+22)-3.(17+28)
8/ -48+48.(-78)+48.(21)
1, 35 . 18 - 5 . 7 . 28
= 35 . 18 - 35 . 28
= 35 . ( 18 - 28 )
= 35 . ( -10 )
= -350
2, 45 - 5 . ( 12 + 9 )
= 40 . 21
= 840
3, 24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
= 24 . 11 - 16 . 19
= 264 - 304
= -40
-4(5-x)=-3(6-x)
-3(x-8)-(2x-7)=35
2. Tính tổng
1+(-2)+3+(-4)+...+49+(-50)
1-2+3-4+...+99-100
2-4+6-8+...+49-50
Tính hợp lý
24(16-5)-16(24-5)
29-(19-13)-19(29*13)
31*(-18)+31*(-81)-31
(-12)*47+(-12)*52+(-12)
13(23+22)-3(17+28)
Tính hợp lí
1)35.18-5.7.28
2)45-5.(12+9)
3)24.(16-5)-16.(24-5)
4)29.(19-13)-19.(29-13)
5)31.(-18)+31.(-81)-31
6)(-12).47+(-12).52+(-12)
7)13.(23+22)-3.(17+28)
8)-48+48.(-78)+48.(-21)
1) 35.18 - 5.7.28
= 35.18 - 35.28
= 35.(18 - 28)
= 35.(-10)
= -350
2) 45 - 5.(12 + 9)
= 45 - 5.12 - 5.9
= 45 - 60 - 45
= (45 - 45) - 60
= 0 - 60
= -60
3) 24.(16 - 5) - 16.(24 - 5)
= 24.16 - 24.5 - 16.24 + 16.5
= (24.16 - 16.24) - (24.5 + 16.5)
= 0 - (24.5 + 16.5)
= -24.5 + 16.5
= 5.(-24 + 16)
= 5.(-8)
= -40
4) 29.(19 - 13) - 19.(29 - 13)
= 29.19 - 29.13 - 19.29 + 19.13
= (29.19 - 19.29) + (19.13 - 29.13)
= 0 + (19.13 - 29.13)
= 19.13 - 29.13
= 13.(19 - 29)
= 13.(-10)
= -130
5) 31.(-18) + 31.(-81) - 31
= 31.(-18 - 81 - 1)
= 31.(-100)
= -3100
6) (-12).47 + (-12).52 + (-12)
= (-12).(47 + 52 + 1)
= (-12).100
= -1200
7) 13.(23 + 22) - 3.(17 + 28)
= 13.45 - 3.45
= 45.(13 - 3)
= 45.10
= 450
8) -48 + 48.(-78) + 48.(-21)
= 48.(-1) + 48.(-78) + 48.(-21)
= 48.(-1 - 78 - 21)
= 48.(-100)
= -4800
Cố gắng lên nhé em Hoàng Mai Hoa
1)35.18-5.7.28
= 35 . 18 - 35 . 28
= 35 . ( 18 - 28 )
= 35 . ( - 10 )
= - 350
1) 35.18 - 5.7.28
= 35.18 - 35.28
= 35.(18 - 28)
= 35.(-10)
= -350
2) 45 - 5.(12 + 9)
= 45 - 5.12 - 5.9
= 45 - 60 - 45
= (45 - 45) - 60
= 0 - 60
= -60
3) 24.(16 - 5) - 16.(24 - 5)
= 24.16 - 24.5 - 16.24 + 16.5
= (24.16 - 16.24) - (24.5 + 16.5)
= 0 - (24.5 + 16.5)
= -24.5 + 16.5
= 5.(-24 + 16)
= 5.(-8)
= -40
4) 29.(19 - 13) - 19.(29 - 13)
= 29.19 - 29.13 - 19.29 + 19.13
= (29.19 - 19.29) + (19.13 - 29.13)
= 0 + (19.13 - 29.13)
= 19.13 - 29.13
= 13.(19 - 29)
= 13.(-10)
= -130
5) 31.(-18) + 31.(-81) - 31
= 31.(-18 - 81 - 1)
= 31.(-100)
= -3100
6) (-12).47 + (-12).52 + (-12)
= (-12).(47 + 52 + 1)
= (-12).100
= -1200
7) 13.(23 + 22) - 3.(17 + 28)
= 13.45 - 3.45
= 45.(13 - 3)
= 45.10
= 450
8) -48 + 48.(-78) + 48.(-21)
= 48.(-1) + 48.(-78) + 48.(-21)
= 48.(-1 - 78 - 21)
= 48.(-100)
= -4800
Cố gắng lên nhé ạ
2/3-6/12+1/4
4/12-18/24+5/2
-5/7*11/9+5/7*4/9
-3/8*13/11-3/8*3/11
2/3-6/12+1/4 = 5/12
4/12-18/24+5/2 = 25/12
-5/7*11/9+5/7*4/9 = -5/9
-3/8*13/11-3/8*3/11 = -6/11
a)2/9-(-4/9)=
b)(-1/24+0,25+1 1/12):(-1/2)2
c)3/13.-5/9+10/13.-5/9+-4/9
Bài 2:
a)-4 1/5:x=5 1/4, b)7/12-5/12.x=1/12
a)2/9-(-4/9)=6/9=2/3
b)(-1/24+0,25+1 1/12):(-1/2)2
=(-1/24+6/24+26/24):(-1/2).2
=31/24.-2.2
=-31/12.2
=-31/6
c)3/13.(-5/9)+10/13.(-5/9)+(-4/9)
=-5/9(3/13+10/13)+(-4/9)
=-5/9.1+(-4/9)
=-1
1.
a)2/9-(-4/9)=6/9
b)(-1/24+0,25+11/12):(-1/2)2
=1,125:-1
=-1,125
c) 3/13.-5/9+10/13.-5/9+-4/9
=-5/9.(3/13+10/13)+4/9
=5/9.1+4/9
=5/9+4/9
=9/9=1
2.
a)-41/5:x=51/4
x=51/41.-41/5
x=-1
vậy x=-1
b)7/12-5/12.x=1/12
5/12.x=1/12+7/12
5/12.x=6/12
x=6/12:5/12
x=6/12.12/5
x=6/5
vậy x=6/5
a,13/24+5/12=
b,4/7-3/8=
c,19/17+13/51
d,26/30-7/15