Đề bài - bài 6 trang 54 tài liệu dạy – học toán 6 tập 2

a

\({{ - 2} \over 3}\)

-8

0

\({7 \over {12}}\)

b

\({4 \over 9}\)

\({{ - 5} \over 8}\)

\({4 \over 7}\)

a . b

\({4 \over {15}}\)

\({3 \over 7}\)

a : b

\({{ - 6} \over 5}\)

a

\({{ - 2} \over 3}\)

\({{ - 8} \over {15}}\)

-8

0

\({7 \over {12}}\)

b

\({4 \over 9}\)

\({{ - 5} \over 8}\)

\({{20} \over 3}\)

\({4 \over 7}\)

\({{36} \over {49}}\)

a . b

\({{ - 8} \over {27}}\)

\({4 \over {15}}\)

\({{ - 160} \over 3}\)

0

\({3 \over 7}\)

a : b

\({{ - 3} \over 2}\)

\({{64} \over {75}}\)

\({{ - 6} \over 5}\)

0

\({{343} \over {432}}\)