Question

tính nhanh:

Answer 1

a: \(=\dfrac{3\cdot6\cdot9\cdot7}{7\cdot12\cdot15}=\dfrac{3\cdot6\cdot9}{3\cdot4\cdot3\cdot5}=\dfrac{3\cdot6}{4\cdot5}=\dfrac{18}{20}=\dfrac{9}{10}\)

b: \(\dfrac{9\cdot6\cdot5}{12\cdot27\cdot15}=\dfrac{3}{4}\cdot\dfrac{1}{3}\cdot\dfrac{2}{9}=\dfrac{1}{4}\cdot\dfrac{2}{9}=\dfrac{1}{18}\)

Answer 2

Answer 3

a)\(=\dfrac{3x6x7x3x3}{7x6x2x3x5}=\dfrac{3x3}{2x5}=\dfrac{9}{10}\)

b)\(=\dfrac{9x6x5}{2x6x3x9x5x3}=\dfrac{1}{2x3x3}=\dfrac{1}{18}\)

Answer 4