a) \(\frac{28\times7-45\times7+7\times18}{45\times14}\)
\(=\frac{7\left(28-45+7\right)}{45\times14}\)
\(=\frac{7\times\left(-10\right)}{45\times14}=\frac{-1}{9}\)
b) \(\frac{12.3-2.6}{4.5.6}\)
\(=\frac{2.6.3-2.6}{4.5.6}\)
\(=\frac{2.6\left(3-1\right)}{2.2.5.6}\)
\(=\frac{2.6.2}{2.2.5.6}\)\(=\frac{1}{5}\)
a)\(\frac{28\times7-45\times7+7\times18}{45\times14}\)
\(=\frac{7\times\left(28-45+18\right)}{45\times14}\)
\(=\frac{7\times1}{45\times14}\)
\(=\frac{1}{90}\)
b)\(\frac{12\times3-2\times6}{4\times5\times6}\)
\(=\frac{12\times\left(3-1\right)}{4\times5\times6}\)
\(=\frac{6\times2\times2}{2\times2\times5\times6}\)
\(=\frac{1}{5}\)
P/s em tham khảo nhé
a/\(\frac{28\cdot7-45\cdot7+7\cdot18}{45\cdot14}\)
\(=\frac{\left(28-45+18\right)\cdot7}{45\cdot14}=\frac{1.7}{45\cdot14}=\frac{1\cdot1}{45\cdot2}=\frac{1}{90}\)
b/\(\frac{12\cdot3-2\cdot6}{4\cdot5\cdot6}=\frac{36-2\cdot6}{4\cdot5\cdot6}=\frac{6\cdot6-2\cdot6}{4\cdot5\cdot6}=\frac{4\cdot6}{4\cdot5\cdot6}=\frac{1}{5}\)
Học tốt !!!
