![](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 \(\frac{2}{3}+y=\frac{11}{12}.5\)
\(\Rightarrow\frac{2}{3}+y=\frac{55}{12}\)
\(\Rightarrow y=\frac{55}{12}-\frac{2}{3}\)
\(\Rightarrow y=\frac{55}{12}-\frac{8}{12}\)
\(\Rightarrow y=\frac{47}{12}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 85 + 11 × 305 = 85 + 3355
= 3440
b) 85 × 11 + 305 = 935 + 305
= 1240
![](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)
\(\left(x+x\times2\right):24=305\)
\(\left(x\times1+x\times2\right):24=305\)
\(\left[x\times\left(1+2\right)\right]:24=305\)
\(\left(x\times3\right)=305\times24\)
\(\left(x\times3\right)=7320\)
\(x=7320:3\)
\(x=2440\)
Vậy \(x=2440\)
\(\left(x+x\times2\right):24=305\)
\(\left(x\times1+x\times2\right):24=305\)
\(x\times\left(1+2\right)=305\times24\)
\(x\times3=7320\)
\(x=7320:3\)
\(x=2440\)
Vậy \(x=2440\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Dat \(S=5+10+15+...+310=5x\left(1+2+3+...+62\right)=5x\frac{\left(62+1\right)x62}{2}=9765\)
cach 2
\(S=\frac{\left(310+5\right)x62}{2}=9765\)
![](https://rs.olm.vn/images/avt/0.png?1311)
đề :
= 305 . (1234 - 234)
=305.1000
=305000
305 x 1234 - 305 x 234
= 305 x ( 1234 - 234 )
= 305 x 1000
= 305000
học tốt