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)
=22/17 +16/27 -5/17 +0,5+7/23
=1+0,5+16/27+7/23
=2977/1242
\(1\frac{5}{17}+\frac{16}{27}-\frac{5}{17}+0.5+\frac{7}{23}\)
\(=1+\frac{5}{17}+\frac{16}{27}-\frac{5}{17}+\frac{1}{2}+\frac{7}{23}\)
\(=1+\frac{16}{27}+\frac{1}{2}+\frac{7}{23}+\left(\frac{5}{17}-\frac{5}{17}\right)\)
\(=\frac{43}{27}+\frac{37}{46}+0\)
\(=\frac{1978}{1242}+\frac{999}{1242}\)
\(=\frac{2977}{1242}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Đề Này Không tính nhanh được đâu bạn
Minh tính Ra kết quả là :
\(\frac{2257}{378}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(A=\frac{\frac{1}{11}-\frac{1}{13}-\frac{1}{17}}{\frac{5}{11}-\frac{5}{13}-\frac{5}{17}}+\frac{\frac{2}{3}-\frac{2}{9}-\frac{2}{27}+\frac{2}{81}}{\frac{7}{3}-\frac{7}{9}-\frac{7}{27}+\frac{7}{81}}\)
\(=\frac{\frac{1}{11}-\frac{1}{13}-\frac{1}{17}}{5\left(\frac{1}{11}-\frac{1}{13}-\frac{1}{17}\right)}+\frac{2\left(\frac{1}{3}-\frac{1}{9}-\frac{1}{27}+\frac{1}{81}\right)}{7\left(\frac{1}{3}-\frac{1}{9}-\frac{1}{27}+\frac{1}{81}\right)}\)
\(=\frac{1}{5}+\frac{2}{7}\)
\(=\frac{7}{35}+\frac{10}{35}\)
\(=\frac{17}{35}\)
Vậy \(A=\frac{17}{35}\)
b) \(B=\frac{5^2}{11.16}+\frac{5^2}{16.21}+\frac{5^2}{21.26}+\frac{5^2}{26.31}+...+\frac{5^2}{56.61}\)
\(=5.\left(\frac{5}{11.16}+\frac{5}{16.21}+\frac{5}{21.26}+...+\frac{5}{56.61}\right)\)
\(=5.\left(\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+\frac{1}{21}-\frac{1}{26}+...+\frac{1}{56}-\frac{1}{61}\right)\)
\(=5.\left(\frac{1}{11}-\frac{1}{61}\right)\)
\(=5.\left(\frac{61}{671}-\frac{11}{671}\right)\)
\(=5.\frac{50}{671}\)
\(=\frac{250}{671}\)
Vậy \(B=\frac{250}{671}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
5 \(\frac{27}{5}\)+ \(\frac{27}{23}\)+ 0,5 \(-\)\(\frac{5}{27}\)+ \(\frac{16}{23}\)
\(\Rightarrow\) \(\frac{52}{5}\)+\(\frac{27}{23}+\frac{1}{2}-\frac{5}{27}+\frac{16}{23}\)
\(\approx\)12
![](https://rs.olm.vn/images/avt/0.png?1311)
\(5\frac{5}{27}+\frac{7}{23}+0,5-\frac{5}{27}+\frac{16}{23}\)
\(=\left(5\frac{5}{27}-\frac{5}{27}\right)+\left(\frac{7}{23}+\frac{16}{23}\right)+0,5\)
\(=5+\frac{23}{23}+0,5=5,5+1=6,5\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(C=\frac{155-\frac{10}{7}-\frac{5}{11}+\frac{5}{23}}{403-\frac{26}{7}-\frac{13}{11}+\frac{13}{23}}+\frac{\frac{3}{5}+\frac{3}{13}-0,9}{\frac{7}{91}+0,2-\frac{3}{10}}\)
\(=\frac{5\cdot\left(31-\frac{2}{7}-\frac{1}{11}+\frac{1}{23}\right)}{13\cdot\left(31-\frac{2}{7}-\frac{1}{11}+\frac{1}{23}\right)}+\frac{\frac{3}{5}+\frac{3}{13}-\frac{9}{10}}{\frac{1}{13}+\frac{1}{5}-\frac{3}{10}}\)
\(=\frac{5}{13}+\frac{3\cdot\left(\frac{1}{5}+\frac{1}{13}-\frac{3}{10}\right)}{\frac{1}{5}+\frac{1}{13}-\frac{3}{10}}\)
\(=\frac{5}{13}+3\)
\(=\frac{44}{13}\)