Question

[Sách Giáo Khoa]

Rút gọn :

a) \(\dfrac{4.7}{9.32}\)                            b) \(\dfrac{3.21}{14.15}\)                     c) \(\dfrac{2.5.13}{26.35}\)

d) \(\dfrac{9.6-9.3}{18}\)                   e) \(\dfrac{17.5-17}{3-20}\)               f) \(\dfrac{49+7.49}{49}\)

Answer 1

[Trần Ngọc Bích Vân]

a) \(\dfrac{4.7}{9.32}=\dfrac{4.7}{9.4.8}=\dfrac{7}{72}\) b) \(\dfrac{3.21}{14.15}=\dfrac{3.7.3}{7.2.3.5}=\dfrac{3}{10}\)

c) \(\dfrac{2.5.13}{26.35}=\dfrac{2.5.13}{2.13.5.7}=\dfrac{1}{7}\) d)\(\dfrac{9.6-9.3}{18}\) \(=\dfrac{9.\left(6-3\right)}{9.2}=\dfrac{9.3}{9.2}=\dfrac{3}{2}\)

e) \(\dfrac{17.5-17}{3-20}=\dfrac{17.\left(5-1\right)}{-17}=-\dfrac{17.4}{17}=-4\) f) \(\dfrac{49+7.49}{49}=\dfrac{49.\left(1+7\right)}{49}=8\)