![](https://rs.olm.vn/images/avt/0.png?1311)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(a,30\cdot6+30\cdot71+20\cdot30\)
=\(30\cdot\left(6+71+20\right)\)
=\(30\cdot97=2910\)
\(b,24\cdot\left(31+119\right)+76\cdot\left(29+121\right)\)
=\(24\cdot150+76\cdot150\)
=\(150\cdot\left(24+76\right)\)
=\(150\cdot100\)
=\(15000\)
\(c,87\cdot23+70\cdot87+43\cdot93\)
=\(87\cdot\left(23+87\right)+43\cdot93\)
=\(87\cdot110+3999\)
=\(9570+3999\)
=13569
a) 15 . 6 . 2 + 3 . 71 . 10 + 20 . 30
= ( 15 . 2 ) . 6 + ( 3 . 10 ) . 71 + 20 . 30
= 30 . 6 + 30 . 71 + 20 . 30
= 30 . ( 6 + 71 + 30 )
= 30 . 107
= 3210
b) 24 . 31 + 24 . 119 + 76 . 29 + 76 . 121
= 24 . ( 31 + 119 ) + 76 . ( 29 + 121 )
= 24 . 150 + 76 . 150
= 150 . ( 24 + 76 )
= 150 . 100
= 15 000
c) 87 . 23 + 43 . 93 + 70 . 87
= 87 . 23 + 70 . 87 + 43 . 93
= 87 . ( 23 + 70 ) + 43 . 93
= 87 . 93 + 43 . 93
= 93 . ( 87 + 43 )
= 93 . 130
= 12 090
![](https://rs.olm.vn/images/avt/0.png?1311)
\(M=\frac{1}{10}+\frac{4}{20}+\frac{9}{30}+\frac{16}{40}+...+\frac{81}{90}\)
\(M=\frac{1}{10}+\frac{2}{10}+\frac{3}{10}+\frac{4}{10}+...+\frac{9}{10}\)
\(M=\frac{\left(9+1\right)\cdot\left(9-1+1\right):2}{10}\)
\(M=\frac{10\cdot9:2}{10}=4,5\)
![](https://rs.olm.vn/images/avt/0.png?1311)
* \(20+65.4=\left(x+75\right):5+30\)
\(\Leftrightarrow20+260-30=\frac{x}{5}+\frac{75}{5}\)
\(\Leftrightarrow20+260-30-\frac{75}{5}=\frac{x}{5}\)
\(\Leftrightarrow235=\frac{x}{5}\Rightarrow x=235.5=1175\)
* \(2248:\left[119-\left(x-6\right)\right]=24\)
\(\Leftrightarrow2248:\left(119-x+6\right)=24\)
\(\Leftrightarrow2248:\left(125-x\right)=24\)
A mình lỡ tay, để mình tính tiếp nhá!
\(\Leftrightarrow125-x=2248:24\Leftrightarrow125-x=\frac{281}{3}\Rightarrow-x=\frac{94}{3}\Rightarrow x=-\frac{94}{3}\)(bài này mình thấy sai sai sao á, nếu mình làm sai thì thông cảm cho mình nhé!
* \(\left(x+70\right):14-40=\left(32.15\right):2\)
\(\Leftrightarrow\left(x+70\right):14=480:2+40\)
\(\Leftrightarrow\frac{x}{14}+5=280\Leftrightarrow\frac{x}{14}=275\Rightarrow x=3850\)
* \(x-4867=\left(175.2050.70\right):25+23\)
\(\Leftrightarrow x-4867-23=\left(175:25\right).\left(2050:25\right).\left(70:25\right)\)
\(\Leftrightarrow x-4890=7.82.\frac{14}{5}\)
\(\Leftrightarrow x-4890=\frac{8036}{5}\Rightarrow x=\frac{8036}{5}+4890=\frac{32486}{5}\)(bài này mình thấy hình như cũng có cái gì đó sai sai luôn hihi!)
![](https://rs.olm.vn/images/avt/0.png?1311)
30=2.3.5
70=2.5.7
42=2.3.7
16=\(^{2^4}\)
48=2^4x3
36=2^2x3^2
81=3^4
![](https://rs.olm.vn/images/avt/0.png?1311)
Trả lời
9^70 < 29^50
2^91 > 5^30
47^25 > 7^55
17^50 < 30^70
81^75 > 30^100
Phân tích các số sau ra thừa số nguyên tố:
a)30 ; 70 ; 42
b)16 ; 48 ; 36 ; 81
c)10 ; 100 ; 1000; 10000
![](https://rs.olm.vn/images/avt/0.png?1311)
a, 30 = 2.3.5
70 = 2.5.7
42 = 2.3.7
b, 16 = 2^4
48 = 2^4 . 3
36 = 2^2 . 3^2
81 = 3^4
c, 10 = 2.5
100 = 2^2 . 5^2
1000 = 2^3.5^3
10 000 = 2^4.5^4
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 64.x + 34.x = 1930
=> (64 + 34).x = 1930
=> 98.x = 1930
=> x = 1930 : 98 = 965/49
b) 119.x + 81.x = 9751000
=> (119 + 81).x = 9751000
=> 200.x = 9751000
=> x = 9751000 : 200 = 48755
a) 64x + 34x = 1930
<=> 98x = 1930
<=> x= \(\frac{965}{49}\)
b) 119x + 81 x = 9751000
<=> 200x = 9751000
<=> x= 48755
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(30=2.3.5;70=2.5.7;42=2.3.7\)
b) \(16=2^4;48=2^4.3;36=2^2.3^2;81=3^4\)
c) \(10=2.5;100=2^2.5^2;10000=2^4.5^4\)
a)30=2.3.5,70=2.5.7,42=2.3.7
b)16=2^4,48=2^4.3,81=3^4
c)10=2.5,100=2^2.5^2,10000=2^4.5^5
chuẩn đó k cho mình đi mà
`81+(-70)+119 +(-30)+1`
`= (81+119)+[(-70)+(-30)] +1`
`= 200+ (-100)+1`
`= 100+1`
`=101`