\(\frac{2}{2.4}+\frac{2}{4.6}+\frac{2}{6.8}=\)
\(\frac{1}{2}-\frac{1}{3}-\frac{2}{3}+\frac{1}{4}+\frac{2}{4}+\frac{3}{4}-\frac{1}{5}-\frac{2}{5}-\frac{3}{5}-\frac{4}{5}+...+\frac{1}{10}+\frac{2}{10}+\frac{3}{10}+...+\frac{9}{10}\)\(+\)\(\frac{9}{10}\)
\(\frac{2}{3}+\frac{2}{15}+\frac{2}{35}+\frac{2}{63}+\frac{2}{99}+\frac{2}{143}\)
viết thêm 4 phân số\(\frac{1}{1};\frac{1}{2};\frac{2}{1};\frac{1}{3};\frac{2}{2};\frac{3}{1};\frac{...}{...};\frac{...}{...};\frac{...}{...};\frac{...}{...}\)
Dãy phân số nào được viết theo thứ tự từ bé đến lớn là :
A. \(\frac{1}{2},\frac{2}{5},\frac{2}{7}\) B. \(\frac{2}{7},\frac{2}{5},\frac{1}{2}\) C. \(\frac{2}{5},\frac{2}{7},\frac{2}{5}\) C. \(\frac{1}{2},\frac{2}{7},\frac{1}{7}\)
\(\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}=\)
\(\frac{2}{3}+\frac{2}{9}+\frac{2}{27}+\frac{2}{81}+\frac{2}{243}=\)
\(\frac{75}{100}+\frac{18}{21}+\frac{19}{23}+\frac{1}{4}+\frac{3}{21}+\frac{13}{32}=\)
\(4\frac{2}{5}+5\frac{6}{9}+2\frac{3}{4}+\frac{3}{5}+\frac{1}{3}+\frac{1}{4}\)
\(\frac{2}{3\cdot5}+\frac{2}{5\cdot7}+\frac{2}{7\cdot9}+.....+\frac{2}{41\cdot43}\)
\(\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{?}{?}=5\)
