73 + 37 =?
6 x 5 =?
8 x 9 =?
tìm x biết
1) 9-25=(7-x)-(25+7)
2) (27-514) -(486-73)+x=7
3) 25+5+37-25+6-29-x=37
4) 14+(-12)+x =10-/-15/+ /-3/
1) 9-25=(7-x)-(25+7)
(7-x)-(25+7)=9-25
(7-x)-(25+7)=-16
(7-x)-32=-16
7-x=-16+32
7-x=16
x=7-16
x=-9
2) (27-514) -(486-73)+x=7
(27-514) -(486-73)+x=7
-487-413+x=7
-1011+x=7
x=7-(-1011)
x=7+1011
x=1018
3) 25+5+37-25+6-29-x=37
25+5+37-25+6-29-x=37
67-25+6-29-x=37
42+6-29-x=37
48-29-x=37
19-x=37
x=19-37
x=-18
4) 14+(-12)+x =10-/-15/+ /-3/
14+(-12)+x =10-15+3
14+(-12)+x =-5+3
14+(-12)+x =-2
2+x=-2
x=-2-2
x=-4
Bài 1: Tính :
4/5 x 6/7 2/9 x 1/2 1/2 x 8/3
7/9 x 6/5 8/7 x 5/9 10/11 x 22/15
Bài 2: Rút gọn rồi tính:
2/6 x 5/3 11/9 x 5/10 3/9 x 6/8
4/9 x 12/16 25/15 x 6/7 6/10 x 15/20
Bài 2:
a: 2/6x5/3=10/18=5/9
b: 11/9x5/10=55/90=11/18
c: 3/9x6/8=1/3x3/4=1/4
d: 4/9x12/16=48/144=1/3
e: 25/15x6/7=5/3x6/7=30/21=10/7
f: 6/10x15/20=90/200=9/20
Bài 1
4/5 x 6/7= 24/35
2/9 x 1/2= 2/18= 1/9
1/2 x 8/3= 8/6= 4/3
7/9 x 6/5= 42/45= 14/15
8/7 x 5/9= 40/63
10/11 x 22/15= 220/165= 4/3
Bài 2
2/6 x 5/3= 1/3 x 5/3=5/9
11/9 x 5/10= 11/9 x 1/2= 11/18
3/9 x 6/8= 1/3 x 3/4 =3/12= 1/4
4/9 x 12/16= 4/9 x 3/4= 12/36= 1/3
25/15 x 6/7= 5/3 x 6/7= 30/21= 10/7
6/10 x 15/20= 3/5 x 3/4= 9/20
bài 1
4/5 x 6/7 = 24/35
2/9 x 1/2 = 1/9
1/2 x 8/3 = 4/3
7/9 x 6/5 = 14/15
8/7 x 5/9 = 14/15
8/7 x 5/9 = 40/63
10/11 x 22/15 = 4/3
Bài 2:Tìm x,biết:
1, 4/5-x=1/3
2, 2/3+5/3x=5/7
3, -12/13x+5=5 1/13
4, x:(-2 1/4)+1,5=-3/4
5,GTTĐ của x -3/4 - 1/4=0
6, 6-GTTĐ của 1/2-x = 2/3
7, (x-1)2=4/9
1) x = 4/5 - 1/3
x = 7/15
2) 5/3.x=1/21
x=1/35
3) -12/13.x = 1/13
x=-1/12
7) th1: x-1=2/3
x = 5/3
Th2: x - 1 = -2/3
x=1/3
Tính nhẩm: 1) 373737 . 73 - 37 . 737373 2)19 . 41414141 - 41 . 19191919 3)123456 . 456789456789 - 456789 . 123456123456 4)250 . 12 . 7 5)24 . 125 . 9 6)125 . 44 . 18 7)8 . 24 . 6 + 12 . 4 . 52 + 2 . 22 . 24 8)18. 58 . 2 - 9 . 27 . 4 + 12 . 69 . 3 9)30 . 85 . 3 + 18 . 72 . 5 - 45 . 37 . 2 - 9 . 20 . 10
1) \(373737.73-37.737373\)
\(=37.10101.73-37.73.10101\)
\(=0\)
2) \(19.41414141-41.19191919\)
\(=19.41.1010101-41.19.1010101\)
\(=0\)
3) \(123456.456789456789-456789.123456123456\)
\(=123456.456789.1000001-456789.123456.1000001\)
\(=0\)
4) \(250.12.7\)
\(=250.4.3.7\)
\(=\left(250.4\right).\left(3.7\right)\)
\(=1000.21\)
\(=21000\)
5) \(24.125.9\)
\(=3.8.125.9\)
\(=\left(3.9\right).\left(8.125\right)\)
\(=27.1000\)
\(=27000\)
6) \(125.44.18\)
\(=125.4.11.2.9\)
\(=\left(125.4.2\right).\left(11.9\right)\)
\(=1000.99\)
\(=99000\)
7) \(8.24.6+12.4.52+2.22.24\)
\(=48.24+48.52+48.22\)
\(=48\left(24+52+22\right)\)
\(=48.98\)
\(=48\left(100-2\right)\)
\(=48.100-48.2\)
\(=4800-96\)
\(=4704\)
8) \(18.58.2-9.27.4+12.69.3\)
\(=36.58-36.27+36.69\)
\(=36\left(58-27+69\right)\)
\(=36.100=3600\)
9) \(30.85.3+18.72.5-45.37.2-9.20.10\)
\(=90.85+90.72-90.37-90.20\)
\(=90\left(85+72-37-20\right)\)
\(=90.100=9000\)
Tính nhanh :
a. 8 x 37 x 5 x 25
b. 48 x 34 + 6 x 66 x 8
c. 17 x [ 13 - 5 ] + 17 x 5
d. 78 x 100 - 100
e. 6 x 17 x 8 + 3 x 37 x 16 + 4 x 46 x 12
f . 47 x 43 + 47 x 73 - 8 x 47 x 2
Mik nhờ các bn giải ra đàng hoàng hộ mik . Mik rất cần , rất gấp ! Mong các bn giupps đỡ . Mik rất mong lời giải của các bn nhé !!!~~
a. 8 x 37 x 5 x 25 = (8 x 25) x 37 x 5
= 200 x 5 x 37 = 1000 x 37 = 37000
b. 48 x 34 + 6 x 66 x 8 = 48 x 34 + 48 x 66 = 48 x ( 34 + 66) = 48 x 100 = 4800
c. 17 x (13 - 5) + 17 x 5 = 17 x 8 + 17 x 5 = 17 x (8 + 5) = 17 x 13 = 221
d. 78 x 100 - 100 = 78 x 100 - 100 x 1 = 100(78 - 1) = 100 x 77 = 7700
e. 6 x 17 x 8 + 3 x 37 x 16 + 4 x 46 x 12
= 48 x 17 + 48 x 37 + 48 x 46
= 48 x (17 + 37 + 46)
= 48 x 100 = 4800
f. 47 x 43 + 47 x 73 - 8 x 47 x 2 = 47 x 43 + 47 x 73 - 47 x 16 = 47 x (43 + 73 - 16) = 47 x 100 = 4700
8×37×5×25=296×5×25=1480×25=37000
48×34+6×66×8=1632+396×8=1632+3168=4800
15×(13-7)+17×5=15×6+17×5=90+85=175
78×100-100=7800-100=7700
37 x 5^4 trên 25 ^ 2
2 ^4 x 2^6 x 3^8 x 9^2 trên 4^4 x 3^11
3 x 9^4 x 9^3 trên 3^2 x 9
125 x 5 x 64 - 25^3 x10 x 4 trên 5^7 x 8
\(\dfrac{37\cdot5^4}{25^2}=\dfrac{37\cdot5^4}{5^4}=37\\ \dfrac{2^4\cdot2^6\cdot3^8\cdot9^2}{4^4\cdot3^{11}}=\dfrac{2^{10}\cdot3^8\cdot3^4}{2^8\cdot3^{11}}=2^2\cdot3=12\\ \dfrac{3\cdot9^4\cdot9^3}{3^2\cdot9}=\dfrac{3\cdot3^8\cdot3^6}{3^2\cdot3^2}=3^{11}\\ \dfrac{125\cdot5\cdot64-25^3\cdot10\cdot4}{5^7\cdot8}=\dfrac{5^3\cdot5\cdot2^6-5^6\cdot2\cdot5\cdot2^2}{5^7\cdot2^3}=\dfrac{5^4\cdot2^3\left(2^3-5^3\right)}{5^7\cdot2^3}=\dfrac{8-125}{5^3}=\dfrac{-117}{125}\)
1. tìm x
a. 71-(33+x)=26
b. (x+73)-26=76
c. 45-(x+9)=6
d. 89-(73-x)=20
e. (x+7)-25=13
f. 198-(x+4)=120
g. 140:(x-8)=7
h. 4(x+41)=400
i. 11(x-9)=77
j. 5(x-9)=350
k. 2x-49=5 .3 mũ 2
l.200-(2x+6)=4 mũ 3
a) 71 - (33 + x) = 26
⇔ 71 - 33 - x = 26
⇔ 38 - x = 26
⇔ x = 38 - 26
⇔ x = 12
b) (x + 73) - 26 = 76
⇔ x + 73 - 26 = 76
⇔ x + 47 = 76
⇔ x = 76 - 47
⇔ x = 29
c) 45 - (x + 9) = 6
⇔ 45 - x - 9 = 6
⇔ 36 - x = 6
⇔ x = 36 - 6
⇔ x = 30
d) 89 - (73 - x) = 20
⇔ 89 - 73 + x = 20
⇔ 16 + x = 20
⇔ x = 20 - 16
⇔ x = 4
e) (x + 7) - 25 = 13
⇔ x + 7 - 25 = 13
⇔ x - 18 = 13
⇔ x = 13 + 18
⇔ x = 31
f) 198 - (x + 4) = 120
⇔ 198 - x - 4 = 120
⇔ 194 - x = 120
⇔ x = 194 - 120
⇔ x = 74
g) 140 : (x - 8) = 7
⇔ x - 8 = 140 : 7
⇔ x - 8 = 20
⇔ x = 20 + 8
⇔ x = 28
h) 4(x + 41) = 400
⇔ x + 41 = 400 : 4
⇔ x + 41 = 100
⇔ x = 100 - 41
⇔ x = 59
i) 11(x - 9) = 77
⇔ x - 9 = 77 : 11
⇔ x - 9 = 7
⇔ x = 7 + 9
⇔ x = 16
j) 5(x - 9) = 350
⇔ x - 9 = 350 : 5
⇔ x - 9 = 70
⇔ x = 70 + 9
⇔ x = 79
k) 2x - 49 = 5.32
⇔ 2x - 49 = 45
⇔ 2x = 45 + 49
⇔ 2x = 94
⇔ x = 94 : 2
⇔ x = 47
l) 200 - (2x + 6) = 43
⇔ 200 - 2x - 6 = 64
⇔ 194 - 2x = 64
⇔ 2x = 194 - 64
⇔ 2x = 130
⇔ x = 130 : 2
⇔ x = 65
a) 71 - (33 + x) = 26
⇔ 33+x=71-26
⇔ 33 + x = 45
⇔ x = 45 - 33
⇔ x = 12
Vậy x=12
b) (x + 73) - 26 = 76
⇔ (x + 73) = 76+26
⇔ x + 73 = 102
⇔ x = 102-73
⇔ x = 29
Vậy x=29
c) 45 - (x + 9) = 6
⇔ x + 9 = 45 - 6
⇔ x+9 = 39
⇔ x = 39 - 9
⇔ x = 30
Vậy x=30
d) 89 - (73 - x) = 20
⇔ 73 - x = 89 - 20
⇔ 73 - x = 69
⇔ x = 73 - 69
⇔ x = 4
Vậy x=4
e) (x + 7) - 25 = 13
⇔ x + 7 = 13 + 25
⇔ x + 7 = 38
⇔ x = 38 - 7
⇔ x = 31
Vậy x=31
f) 198 - (x + 4) = 120
⇔ x + 4 = 198 -120
⇔ x + 4 = 78
⇔ x = 78 - 4
⇔ x = 74
Vậy x=74
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
( 5 x 6 + 7 - 37 ) x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9+ 10 )
Ai tích mk mk tích lại
( 5 x 6 + 7 - 37 ) x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 )
= ( 30 + 7 - 37 ) x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 )
= 37 - 37 x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 )
= 0 x 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
= 0
( 5 x 6 + 7 - 37 ) x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 )
= 0 x ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 )
= 0
(5 x 6+7-37) x (1+2+3+4+........+10)
=(30+7-37) x (1+2+3+.......+10)
=(37-37) x (1+2+3+........+10)
=0 x (1+2+3+.........+10)
=0