![](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)
24 hay là 2( số nhân với mẫu rồi cộng tử) rùi đến 4 phần 5
![](https://rs.olm.vn/images/avt/0.png?1311)
\(2\frac{4}{5}.x-50:\frac{2}{3}=51\)
\(\frac{14}{5}.x-50:\frac{2}{3}=51\)
\(\frac{14}{51}.x=51+50:\frac{2}{3}\)
\(\frac{14}{51}.x=51+75\)
\(\frac{14}{51}.x=126\)
\(x=126:\frac{14}{51}\)
x=459
Vậy x=459
\(\frac{2}{3}.x=\frac{5}{12}=>x=\frac{5}{12}:\frac{2}{3}=\frac{5.3}{12.2}=\frac{15}{24}\)=\(\frac{3}{8}\)
vậy x=3/8
![](https://rs.olm.vn/images/avt/0.png?1311)
a){x-[52+(35-80.3)3-51]50+14}=20
=>x-[25+(243-240)3-51]50+14=20
=>x-[25+33-51]50+14=20
=>x-[25+27-51]50+14=20
=>x-[52-51]50+14=20
=>x-150+14=20
=>x-1+14=20
=>x-1=20-14
=>x-1=6
=>x=6+1
=>x=7
![](https://rs.olm.vn/images/avt/0.png?1311)
Đề sai r, từ \(x_1;x_2;x_3;...;x_{51}\) có 51 số, chia thành 2 nhóm sẽ thừa 1 số, mà đề bài said: \(x_1+x_2=x_3+x_4=x_5+x_6=...=x_{50}+x_{51}\) vẫn đủ số ->vô cmn lí
Sửa đề
Ta có : x1 + x2 + x3 + x4 + ... + x51 = 0
Xét tổng : \((x_1+x_2)+(x_3+x_4)+...+(x_{49}+x_{50})=1\cdot25=25\)\((\)có 25 cặp\()\)
Tổng x1 + x2 + x3 + x4 + ... + x51 = 0
Hay 25 + x51 = 0
x51 = 0 - 25
x51 = -25
Khi đó x50 + x51 = 1 thay bằng x50 + -25 = 1
=> x50 = 1 - \((\)- 25\()\)
=> x50 = 26
Vậy x50 = 26
Chúc bạn học tốt :>
![](https://rs.olm.vn/images/avt/0.png?1311)
Bài toán sai
bài toán đúng là x+(x+1)+(x+2)+(x+3)+...+19+20=20
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(a,\dfrac{-1}{8}=\dfrac{3}{x}\\ \dfrac{3}{-24}=\dfrac{3}{x}\\ x=-24\\ b,\dfrac{x}{3}=\dfrac{3}{x}\\ x.x=3.3\\ x^2=9\\ x=\pm3\\ c,\dfrac{3}{4}.x=1\dfrac{1}{2}\\ \dfrac{3}{4}.x=\dfrac{3}{2}\\ x=\dfrac{3}{2}:\dfrac{3}{4}\\ x=2\\ d,x-\dfrac{3}{10}=\dfrac{7}{15}:\dfrac{3}{5}\\ x-\dfrac{3}{10}=\dfrac{7}{9}\\ x=\dfrac{7}{9}+\dfrac{3}{10}\\ x=\dfrac{97}{90}\\ e,\dfrac{-4}{7}-x=\dfrac{-8}{3}.\dfrac{3}{7}\\ \dfrac{-4}{7}-x=\dfrac{-8}{7}\\ x=\dfrac{-4}{7}+\dfrac{8}{7}\\ x=\dfrac{4}{7}\\ \)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\left(2\frac{4}{5}x-50\right)\div\frac{2}{3}=51\)
\(\frac{14}{5}x-50=51\times\frac{2}{3}\)
\(\frac{14}{5}x-50=34\)
\(\frac{14}{5}x=84\)
\(x=84\times\frac{5}{14}\)
\(x=30\)
\(a,\left(2\frac{4}{5}.x-50\right):\frac{2}{3}=51\)
\(\left(\frac{14}{5}.x-50\right):\frac{2}{3}=51\)
\(\frac{14}{5}.x-50=51\times\frac{2}{3}\)
\(\frac{14}{5}.x-50=34\)
\(\frac{14}{5}.x=34+50\)
\(\frac{14}{5}.x=84\)
\(x=84:\frac{14}{5}\)
\(x=\frac{405}{14}\)
\(\left(2\frac{4}{5}.x-50\right):\frac{2}{3}=51\)
\(\Leftrightarrow\)\(\frac{14}{5}.x-50=51.\frac{2}{3}=34\)
\(\Leftrightarrow\)\(\frac{14}{5}x=34+50=84\)
\(\Leftrightarrow\)\(x=84:\frac{14}{5}=30\)
Vậy....
\(\left(2\frac{4}{5}x-50\right):\frac{2}{3}=51\)
\(\left(\frac{14}{5}x-50\right)=51\times\frac{2}{3}\)
\(\left(\frac{14}{5}x-50\right)=34\)
\(\frac{14}{5}x=34+50\)
\(\frac{14}{5}x=84\)
\(x=84:\frac{14}{5}\)
\(x=30\)