1.
\(\frac{3}{5}+\left\{\frac{2}{8}+\frac{2}{5}+\frac{6}{8}\right\}\)
\(=\frac{3}{5}+\left(\frac{10}{40}+\frac{36}{40}+\frac{30}{40}\right)\)
\(=\frac{3}{5}+\frac{76}{40}\)
\(=\frac{24}{40}+\frac{76}{40}\)
\(=\frac{100}{40}=\frac{5}{2}\)
2.
\(3\frac{2}{9}-\left\{1\frac{5}{8}+1\frac{2}{9}\right\}\)
\(=\frac{29}{9}-\left\{\frac{13}{8}+\frac{11}{9}\right\}\)
\(=\frac{29}{9}-\left\{\frac{117}{72}+\frac{88}{72}\right\}\)
\(=\frac{29}{9}-\frac{205}{72}\)
\(=\frac{232}{72}-\frac{205}{72}\)
Chúc cậu học tốt !!!
\(=\frac{27}{72}=\frac{3}{8}\)