12/6 x 15/34 x 17/45
11/6 x 12/22 x 13/39
Bai3: Tính
b. 4 x 6 x 10 x 12 x 15/ 4 x 12 x 5 x 24 x 30 =
c. 34 x 101 x 2005/ 17 x 202 x 4010=
d.6 x 8 x 11 x 13 x 17/ 33 x 16 x 17 x 26 =
b. \(\dfrac{4.2.3.5.2.6.2.5.3}{4.3.4.5.6.4.5.6}=\dfrac{1}{4}\)
c. \(\dfrac{17.2.101.2005}{17.2.101.2.2005}=\dfrac{1}{2}\)
d. \(\dfrac{2.3.4.2.11.13.17}{3.11.4.4.17.13.2}=\dfrac{1}{2}\)
a)\(\dfrac{4\times6\times10\times12\times15}{4\times12\times5\times24\times30}=\dfrac{2}{2\times2\times2}=\dfrac{2}{8}=\dfrac{1}{4}\)
b)\(\dfrac{34\times101\times2005}{17\times202\times4010}=\dfrac{2}{2\times2}=\dfrac{2}{4}=\dfrac{1}{2}\)
c)\(\dfrac{6\times8\times11\times13\times17}{33\times16\times17\times26}=\dfrac{6}{3\times2\times2}=\dfrac{1}{2}\)
2x+20=-22
-(-30)-(-x)=13
-(-x)+14=12
x+20=-(-23)
15-x+17=-(-6)+|-12|
-|-5|-(-x)+4=3-(-25)
2x+20=-22
=> 2x = -22 - 20
=> 2x = -42
=> x = -42 : 2
=> x = -21
Vậy x = -21
2x+20=-22
2x=-22-20
2x=-42
x=-42:2
x=-21
-(-30)-(-x)=13
30+x=13
x=13-30
x=-17
-(-x)+14=12
x+14=12
x=12-14
x=-2
x+20=-(-23)
x+20=23
x=23-20
x=3
15-x+17=-(-6)+|-12|
15+17+x=6+12
32+x=18
x=18-32
x=-14
-|-5|-(-x)+4=3-(-25)
-5+x+4=3+25
-5+4+x=28
-1x=28
x=28:(-1)
x=-28
cam on moi nguoi nhe
số 1 tính nhanh A 78 x 31 78 x 24 78 x 17 22 x 72C 53 x 39 47 x 39 53 x 21 47 x 21B 35 x 34 35 x 86 65 x 75 65 x 45D 27 x 332 68 x 27 73 x 332 68 x 73E 2 x 53 x 12 4 x 6 x 37 2 x 38 x 12F 3 x25 x 8 4 x 6 x 37 2 x 38 x 12
Tính bằng cách thuận tiện nhất:
6/15 x 45/12 x 11/34 x 17/33
Ta có:
=\(\dfrac{6x45x11x17}{15x12x34x33}\)
= \(\dfrac{6x15x3x11x17}{15x6x2x17x2x11x3}\)
= \(\dfrac{1}{2x2}\)
=\(\dfrac{1}{4}\)
Những chữ x ở trên là dấu nhân nhé
số 1 : tính nhanh
A = 78 x 31 + 78 x 24 + 78 x 17 + 22 x 72
C = 53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
B = 35 x 34 + 35 x 86 + 65 x 75 + 65 x 45
D = 27 x 332 + 68 x 27 + 73 x 332 + 68 x 73
E = 2 x 53 x 12 + 4 x 6 x 37 + 2 x 38 x 12
F = 3 x25 x 8 + 4 x 6 x 37 + 2 x 38 x 12
A = 78 x 31 + 78 x 24 + 78 x 17 + 22 x 72
A = 78 x ( 31 + 24 + 17 ) + 22 x 72
A = 78 x 72 + 22 x 72
A = 72 x ( 78 + 22 )
A = 72 x 100
A = 7200
C = 53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
C = 39 x ( 53 + 47 ) - 21 x ( 53 - 47 )
C = 39 x 100 - 21 x 6
C = 3900 - 126
C = 3774
ko pc tui thua bn 1 lp
A = 78 x 31 + 78 x 24 + 78 x 17 + 22 x 72
A = 78 x ( 31 + 24 +17 ) + 22 x 72
A = 78 x 72 + 22 x 72
A = 72 x ( 78 + 22 )
A = 72 x 100
A = 7200
Tính bằng cách thuận tiện nhất. A,15/34 x 5/17 + 19/34 x 5/17 B,13/12 + 1/3 + 7/12 Giải chi tiết giúp mik nhen:<
$#Shả$
`A)=5/17xx(15/34+19/34)`
`=5/17xx1=5/17`
`B)=(13/12+7/12)+1/3`
`=5/3+1/3=2`
X : 7 + 20 = 17 x 49 + 17 x 51 287 - ( X + 34) x 3 - 25 = 142 13 x X + 15 x X + 12 x X = 120
1) x : 7 + 20 = 17 x 49 + 17 x 51
x : 7 +20 = 17 x ( 49+51)
x : 7 +20 =1700
x : 7 = 1700 - 20 =1680
x = 1680 x 7 =11 760
2) 287 - ( x+ 34) x 3 - 25 = 142
287-(x+34)x3 = 142 + 25 =167
( x+34) x 3 = 287 - 167=120
x + 34 = ``120 : 3 =40
x = 40 - 34 = 6
3)13x + 15x + 12x = 120
40x = 120
x = 120 : 40 = 3
tính bằng cách thuận tiện nhất
6/15 x 45/12 x 11/34 x 17/33Tìm x:
a) (x+13)/34=12/17
b)x * 1/6 +1/3 * 3/4 = 7/9