Đề bài

Thực hiện phép tính:

a) $0,58\,.\,{7^2} - \left( { - 7} \right)\,.\,\left( { - 0,7} \right)\,.\,15,8;$

b) $0,05\,:\,0,5 + 7\,:\,0,7 + 0,9:0,009;$

c) $\frac{9}{{11}}\,.\,\frac{{92}}{{121}} + \frac{2}{{ - 121}}\,.\,\frac{9}{{11}}\, + \frac{{31}}{{121}}\,.\,\frac{9}{{11}};$

d) $\frac{{20\,212\,021}}{{2\,021}}\,.\,\frac{{2\,020}}{{20\,202\,020}}.\frac{{{2^3}}}{{{3^2}}}\,.\,\frac{{ - 3}}{{{2^2}}}\,$