Thực hành 2 trang 20 Toán 6 Chân trời sáng tạo Tập 2: Tínha) - 2/7 : 4/7 b) -4/5 :3/11c) 4: 2/5 d) 15/-8 : 6...

Tính.

a) $\frac{{ - 2}}{7}:\frac{4}{7}$ b) $\frac{{ - 4}}{5}:\frac{{ - 3}}{{11}}$

c) $4:\frac{{ - 2}}{5}$ d) $\frac{{15}}{{ - 8}}:6$

$\frac{a}{b}:\frac{c}{d} = \frac{a}{b}.\frac{d}{c}$

a) $\frac{{ - 2}}{7}:\frac{4}{7} = \frac{{ - 2}}{7}.\frac{7}{4} = \frac{{ - 2}}{4} = \frac{{ - 1}}{2}$

b) $\frac{{ - 4}}{5}:\frac{{ - 3}}{{11}} = \frac{{ - 4}}{5}.\frac{{11}}{{ - 3}} = \frac{{ - 44}}{{ - 15}} = \frac{{44}}{{15}}$

c) $4:\frac{{ - 2}}{5} = 4.\frac{5}{{ - 2}} = \frac{{20}}{{ - 2}} = - 10$

d) $\frac{{15}}{{ - 8}}:6 = \frac{{15}}{{ - 8}}.\frac{1}{6} = \frac{{ - 15}}{{48}}= \frac{{ - 5}}{{16}}$.