Các câu hỏi tương tự
Tính nhanh
\(A=\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+...+\frac{1}{120}\)
Tìm A biết :
\(\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+........+\frac{1}{120}\)= A
Giúp mik nhanh nha
1,Tính nhanh
a,3x\(\left(\frac{1}{7}+\frac{1}{3}-\frac{3}{14}\right):\frac{11}{14}\)
b,\(\left(\frac{21}{8}+\frac{1}{2}\right):\frac{5}{6}\)
3,Tìm x,biết
a,\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+......+\frac{2}{x\cdot\left(x+1\right)}=\frac{2016}{2018}\)
b,720:\(720:[41-\left(2\cdot x-5\right)]=120\)
frac{14}{16} - frac{6}{21}frac{9}{22} - frac{9}{33}frac{8}{15}+ frac{4}{21}frac{15}{24}+2frac{4}{5}-frac{1}{3}+frac{1}{2}frac{5}{6}+frac{3}{8}+frac{1}{10}frac{1}{2}+frac{1}{6}+frac{1}{12}+frac{1}{20}+frac{1}{30}
Đọc tiếp
\(\frac{14}{16}\) - \(\frac{6}{21}\)
\(\frac{9}{22}\) - \(\frac{9}{33}\)
\(\frac{8}{15}\)+ \(\frac{4}{21}\)
\(\frac{15}{24}+2\)
\(\frac{4}{5}-\frac{1}{3}+\frac{1}{2}\)
\(\frac{5}{6}+\frac{3}{8}+\frac{1}{10}\)
\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}\)
Tính nhanh
a)\(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
b)\(\frac{5}{9}x\frac{1}{2}x\frac{5}{9}x\frac{6}{4}\)
c)\(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
d)\(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
tính nhanh
\(a,\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
\(b,\frac{5}{9}x\frac{1}{2}+\frac{5}{9}x\frac{6}{4}\)
\(c,\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
\(d,\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
Tính nhanh
a)\(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
b)\(\frac{5}{9}x\frac{1}{2}+\frac{5}{9}x\frac{6}{4}\)
c)\(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
d)\(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
Chứng minh : \(\frac{1}{1}-\frac{1}{1}+\frac{1}{2}-\frac{1}{3}+\frac{1}{5}-\frac{1}{8}+\frac{1}{13}-\frac{1}{21}+\frac{1}{34}-\frac{1}{55}+...< \frac{3}{10}\).
Tính: \(\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+...+\frac{1}{120}\)= ?