90 x 9 : 2 = ?
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. \(\dfrac{x}{5}=\dfrac{8}{10}\)
\(\Rightarrow10x=8.5\)
\(\Rightarrow10x=40\)
\(\Rightarrow x=\dfrac{40}{10}=4\)
b. \(\dfrac{9}{x}=\dfrac{90}{100}\)
\(\Rightarrow9.100=90x\)
\(\Rightarrow900=90x\)
\(\Rightarrow x=\dfrac{900}{90}=10\)
c. \(17+\dfrac{x}{35}=\dfrac{5}{7}\)
\(\Rightarrow\dfrac{595+x}{35}=\dfrac{25}{35}\)
\(\Rightarrow595+x=25\)
\(\Rightarrow x=25-595=-570\)
d. \(x:\dfrac{5}{27}=\dfrac{2}{9}\)
\(\Rightarrow\dfrac{27x:5}{27}=\dfrac{6}{27}\)
\(\Rightarrow27x:5=6\)
\(\Rightarrow27x=5.6\)
\(\Rightarrow27x=30\)
\(\Rightarrow x=\dfrac{30}{27}=\dfrac{10}{9}\approx1,11\)
![](https://rs.olm.vn/images/avt/0.png?1311)
90 + 90 = 180
2 x 2 = 4
9 x 9 = 81
8 x 8 = 64
200 x 1860 = 336 000
89 x 22 = 1958
88 x 11 = 968
1980 x 1980 + 1980 x 2980 = 9 820 800
20000 x 400 = 8 000 000
9960 x 2235 = 22 260 600
90 + 90 = 180
2 x 2 = 4
9 x 9 = 81
8 x 8 = 64
200 x 1860 = 372000
89 x 22 = 1958
88 x 11 = 968
1980 x 1980 + 1980 x 2980 = 9820800
20000 x 400 = 8000000
9960 x 2235 =22260600
k mik nha
chúc bạn hok giỏi
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\left(x+1\right)+\left(x+2\right)+...+\left(x+9\right)=90\)
Ta có 9 SSH (từ 1 đến 9)
9.x+(1+2+3+...+9)=90
9x+(9+1).9:2=90
9x+45=90
9x=90-45=45
x=45:9
x=5
(x+1)+(x+2)+...+(x+9)=90
Ta có 9 SSH (từ 1 đến 9)
9.x+(1+2+3+...+9)=90
9x+(9+1).9:2=90
9x+45=90
9x=90-45=45
x=45:9
x=5
![](https://rs.olm.vn/images/avt/0.png?1311)
bằng 405
=405 bạn nhé